JPS5811005B2 - Radiant energy - method for obtaining information about the position of a reflecting object and device used therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally relates to a method and apparatus for measuring the position of an object and the surface position of an object.

More particularly, it relates to using radiant energy to measure distance to and obtain position information about objects that reflect radiant energy.

US Pat. Nos. 3,936,649 and 3,962,588 disclose methods for generating signals for use in determining the position coordinates of objects or surfaces that reflect radiant energy.

In a preferred embodiment, the reticle has a distinct series of adjacent meshes.

A light source is placed on one side of the reticle at known position coordinates.

A photographic image obtained from an unknown location shows the reticle with a light source placed in perspective relationship from the unknown location within the mesh, allowing the generation of signal pairs.

Each signal has a number of time intervals corresponding to the number of meshes along a defined axis, and in one such time interval the meshes in the perspective relationship are identified and displayed.

This signal pair information, along with the position of the light source, can be used for triangulation to determine the position coordinates of the unknown position.

The reticle is encoded by placing distinguishable elements on selected meshes to facilitate photographic image analysis and to facilitate separation, especially in areas where the mesh network includes a large number of meshes.

In this embodiment, the signal generated from the photographic image also contains encoded information, so that in order to find the meshes in the perspective relationship, it is only necessary to look at the sequence of the meshes divided in this way, You only need to look at a smaller number of meshes than the entire tsuranari.

Another prior art is disclosed in US Pat. No. 3,866,052.

In one implementation of the method, the isobody is irradiated from a common location across a series of masks.

Each mask is adapted to transmit a different amount of radiant energy.

Photographic images are generated and a signal is generated indicating the number of photographic images.

These photographic images also contain preselected points on the surface of the object, and these points can be reconstructed from the photographic images.

Prior art is also disclosed in US Patent Application Nos. 608,265 and 608,266.

The latter of these are similar to those disclosed in the aforementioned U.S. Pat. No. 3,866,052, except that moving a projector translates a linear pattern of radiant energy across the surface of the object. It's different.

A device for emitting patterned light in space by a masked light source to detect direction is disclosed in U.S. Pat.
No. 99675 and No. 3704070.

In these devices, an observer within the illuminated space can determine the angular orientation relative to the light source by detecting the on-off state of the received radiation.

In this case, a light source at a fixed position is turned on and off by a shutter, and light is projected through the chain of coded masks.

Note in the latter of these patents that a single mask can be moved relative to a light source in a fixed position and its space can be encoded with light.

It is an object of the present invention to improve the method and apparatus for using a radiant energy source to obtain a liquid relative to the position of an object in a space.

In accomplishing this and other objects, the present invention provides a method for moving a diverging radiant energy pattern having different adjacent portions such that such pattern portions are sequentially incident on an object.

The emitted radiant energy reflected from the object is collected at a common location and produces an output signal that is a measure of the change in the energy so collected as a function of time, and which signal determines the distance from the origin of the pattern divergence. can be determined.

A photovoltaic array, which is a plurality of strings of photovoltaic cells arranged in a relationship that looks into the object along different axes, allows such output signals to be further indicative of object position relative to such different axes.

The radiant energy pattern is preferably encoded so that this additional position information is more easily obtained.

The present invention will be explained in more detail below using the accompanying drawings.

In Figures 1, 1a and 2 a position measuring device 10 is shown.

10 has a suspension support member 12 adapted to receive the mask 16 by an internal track 14 and to support the mask 16 for translation along the translational axis T of FIG.

Drive disk 18 is selectively rotated to translate mask 16 to apply voltage to a motor and drive (not shown).

The light source 20 may include a lamp 20a and a lens arrangement, and a frame 22 and ribs 2 for translation together with the mask 16.
4a and 24b.

The photovoltaic array device 26 has a lens 26a and a hood 26b, and is fixedly supported by a base 28.

Device 26 includes photovoltaic cells PC1-PC14.

FIG. 1 shows examples of these arrangement patterns.

In this figure, seven pieces are connected along the translational axis T,
Two pieces are connected in the direction that crosses the T.

The mask 16 includes light-transmissive or semi-transparent molecules 1 to T7.
and other parts NT1 to NT6.

NT1 to NT6 separate T1 to T7, respectively.

Parts NT1 to NT6 are preferably opaque (non-transparent), but may have a different light transmittance than part molecules 1 to T7 depending on the case.

In FIG. 2, the space V is defined by a plane P1. parallel to the axis T. P2
and P3.

In one embodiment of the invention, the mask 16 is in the form of a first region P1-1 . P1-3. P1-
5°P1-7. P1-9. P1-11 and P1-13
(corresponding to partial molecules 1 to T7) are irradiated by the light source 20, while regions P1-2. P1-4. P1-6. P1-8,
P1-10 and P1-12 (corresponding to portions NT1 to NT6) are not irradiated, and furthermore, the linear widths of all these regions on the plane P1 are all equal, that is, the linear width of P1-1 is P1- Partial molecules 1 to T7 and NT1 to NT6 so that the width in the linear direction is equal to or less than 2.
The width of each is selected.

Such selective emission of divergent radiant energy from the light source 20 into the space V is caused by the light transmissive portions of the mask and non-(low) This can be achieved by ensuring that the ranges of the transparent parts each have the same linear width.

If the mask 16 is configured in this way, areas P2-1 (irradiated) and P2-2 (not irradiated) on the plane P2 will also have the same width in the linear direction, and areas P2-1 (irradiated) and P2-2 (not irradiated) on the plane P2 will also have the same width in the linear direction. The same applies to areas P3-1 (irradiated) and P3-2 (not irradiated).

In this embodiment, the selectively illuminated plane P1.
P2 and P3 are defined such that these planes are outside the translational axis T and at distances X1 . X2 and X3
Specify a location that is far away.

The time it takes for the irradiation pattern or its common portion to scan any distance in the translational axis direction on the plane P1 is the same and therefore serves as an index of the distance X.

Similarly, the scanning times for arbitrary translation axis distances on the planes P2 and P3 are the same time, different from that for P1, and these times serve as indices for the distances X2 and X3, respectively.

For purposes of illustration, the positions of the radiant energy reflecting objects O1, O2 and O3 are shown in FIG. 2 and FIG. 3 of the same dimensions.

With respect to the reference position R, the object O1 is at a distance X1 towards the outside of R (on the plane P1) and a distance Z1 . It is located at a distance Y1 from R in the direction of axis T.

O2 is the distance X2. from the reference position. Similarly, O3 is defined by distance X3. Defined by Y3 and Z3.

Translate the mask 16 and the light source 20 to the right from the position shown in solid lines in FIG. By continuously translating the mask and light source to the left until they are at the position shown by the dashed line on the left side of Figure 2,
The entire radiation pattern generated by the mask and light source is defined as object O1.
, O2 and O3.

In such a translation, the object O1 has masked molecules 1~
Although they are sequentially irradiated by the light emitted from T7, since the mask portions NT1 to NT6 are arranged between the light source and the object O1, periods of non-irradiation (or different degrees of irradiation) of the object O1 are interposed between them.

Therefore, one photovoltaic cell (PC7) of the photovoltaic array device 26, which is arranged at a fixed position with respect to the object O1, is periodically excited in transparent relation to O1 through the lens 26a.

The excitation time T of the photocell of device 26 is related to the distance X from position R by the following equation:

where v is the translational velocity of the mask and light source, T is the on/off time of the mask pattern detected by device 26, Δ
is the divergence angle of the pattern.

The divergence angle refers to the degree of non-parallelism of the light beams emitted from the light-transmitting portions that move sequentially along the translational axis.

In the case of the embodiment shown in FIG. 2, Δ is (P1-1), respectively.
/X1. (P2-1)/X2. (P3-1)/X3. (
P1-2)/Xi, etc.

In translation of the pattern, the photovoltaic array device 26 moves from O1 to
Detect the energy reflected by O3.

Furthermore, the excitation time of the photovoltaic cell becomes longer in proportion to the distance X from the position R.

Therefore, the object O2 that is closer to R than the object O3 is the object O
3 will cause the photocell to blink at a greater rate than the rate at which the photocell will blink.

Similarly, Ol will cause the photocell to flash at a greater rate than O2.

Therefore, the space V can be considered to consist of positions that can all be defined by a plane parallel to the translational axis T, and objects on such a plane can be defined as
Each has a constant reflection period.

Therefore, according to the present invention, instead of determining the distance using the above-mentioned formula, the distance can be easily determined using a correlation detection technique or a counting technique.

To do this, the space in which this technique is applied must be calibrated by storing facsimiles of objects at a known distance from a position R and the signals reflected by them to the photovoltaic array 26. Must be.

Each such facsimile has a corresponding distance Such facsimile signals can be compared against each other until an indication of distance X is given.

In counting techniques, the number of pulses received within a certain time unit uniquely determines the distance.

This will be discussed in more detail below.

FIG. 4 shows the back side of the photovoltaic array 26 with the circuit lines LPC1-LPC14 emanating from the photovoltaic cells, respectively.

All of these lines are capacitively coupled to the amplifier.

For example, line LPC8 is connected to amplifier 32 through capacitor C.

The output of amplifier 32 selectively represents the photovoltaic cells of photovoltaic array 26 excited with the radiant energy reflected by the object.

For example, if the output signal 34 of the amplifier in line LPG7 (not shown) provides an output signal based on the energy reflected from object O1, then PC7 is energized and in this case the object is shown in FIGS. It will be on the line S.

For example, the output of amplifier 32 on line 36 is
can be processed directly to obtain information about (the plane at that distance).

Once the line S and the plane P1 as a plane of distance X including the object O1 are determined, the object O1 can be positioned in the space V as the intersection of this line and the plane.

A line like this passes through. If the position of the node of the lens 26a is known with respect to the reference position R, the position of the object O1 with respect to R can be easily determined.

In this implementation, line 36 applies its output in common to filters 38, 40 and 42.

These filters are bandpass filters with band frequency limits shown in FIG. 4 to facilitate the separation of reflections from objects at different X distances onto a single photovoltaic cell.

For example, if the object is between position R and plane P1, filter 38 directs the signal on line 36 to line 44a.

The signals on lines 44a, 44b and 44c can be examined by the correlation detection techniques described above for frequency content, or alternatively can be processed as described below with reference to FIGS. 7.8 and 10.

The capacitive coupling of line LPC8 blocks stationary signal components attributable to background light, so background illumination is not significant as long as saturation is avoided.

In a preferred embodiment using an uncoded mask according to the invention, mask 16 was used.

That is, an equally weighted planar mask was used that defined a linearly symmetrical divergent radiant energy pattern in a plane parallel to the translational axis.

An uncoded mask structure that can be used instead of this is the second a,
Shown in Figure 2b.

In FIG. 2a, the uncoded mask 16' is the lamp 20
It has a circular shape centered at a.

The optically transparent portion and the non-transparent portion (for example, T'1 and T'1) of this mask 16' have the same arc length.

Three different objects O4, O5 and O6 on plane P1'
shows.

When the mask 16' is moved to the left from the position of FIG. 2a,
The responses from these objects vary uniquely.

In the response of object O6, the on-off-on pattern initially has a long time Tc, but as the movement progresses, this time decreases.

The response of object O4 begins with a shorter time TA, but this time increases as the movement progresses.

The response of object O5 begins at a longer time TB than for object O4, assuming that the mask 16' extends further counterclockwise, and this time increases as the movement progresses.

For similar reasons, this is true for all planes parallel to plane P1' that lie within the illuminated space.

Therefore, as can be readily seen, each location within this illuminated space will have a response pattern that is easily discernible by the correlation detection techniques described above.

A special case in which when the entire illumination pattern passes through each of the objects O4, O5 and O6 in the manner described with respect to FIG. 2, all objects exhibit a response with the same pattern, only delayed in time. exists.

This is the case when the object is sequentially irradiated with O5, O4, and O6.

Therefore, the positions of all points on the plane R1 can be determined from the times of the occurrence data.

This is true for all points on all planes parallel to P′1, and the response pattern from the object also changes on plane R1 depending on the distance outward from the reference plane P0 in FIG. will be the same except that the response pattern from the point will be expanded or contracted in time.

In section 2b, the non-encoded mask 16'' has adjacent light-transmissive portions and non-transparent portions of different lengths (e.g. T''
1 and NT''1), so that the plane P1'' defines the object position such that the pattern scanning time or the intersection of the patterns is the same.

The analysis of the object response induced by the use of mask 16'' is similar to that described with respect to mask 16 in FIG.

In FIG. 5, the code generation circuit 50 includes individual stages S
The circuit 50 includes a send register consisting of R1 to SR4, and the circuit 50 outputs the outputs of stages SR3 and SR4 to exclusive outputs.
It is connected to the R gate 52.

The output of 52 is applied to register stage SR1 through inverter I54.

To shift the contents of the send register, a clock pulse CP is applied to stage SR1 of the register.

Assuming that each stage has the contents shown in the first row of the table of FIG. During the 15 shift cycles from CP1 to CP15, the stage contents will be as shown in the remaining rows of the clothes.

If the stage SRI is observed in units of 4-bit strings, the contents will change according to the 4-bit pattern shown on the left side of the table in FIG.

Therefore, at CF2, this send register contains the pattern 0000, which is 0 in decimal representation.

In this pattern, the contents of each SR are sequentially shifted in CF2.

As another example, in the case of CPS, this register contains pattern 1101, which is 13 in decimal notation.

In this pattern, the contents of each SR are sequentially shifted during CPS.

Considering another aspect of the invention, the region of space examined includes:
The unique decimal representation pattern of FIG. 5 can be assigned in the manner described in the description of FIG. 3 with respect to plane P3.

In this case, the mask should be as shown in FIG.
Adapt the illumination of the space V to the encoding of the figure form.

The mask 56 in FIG.
and lower light-transmitting moieties 20 to T31.

Furthermore, the upper half of this mask includes optically transparent encoding submolecules E1 to TE5, and the lower half includes optically transparent encoding partial molecules E6 to TE9.

For purposes of explanation, consider that adjacent optically transparent portions define a cell therebetween.

If a coding part is placed between such adjacent parts, such a cell is considered "full", and a cell without a coding part is considered "empty". I think so.

Similar to the mask of FIG. 1, the mask 56 provides Pl-1, Pl-2, etc. occupying equal planar areas, each corresponding to one cell of the mask.

In Figure 6a, empty cells are identified as 0 and filled cells as 1.

Upon receiving energy from an object in perspective through the light source 20 and the partial molecule 8, the photovoltaic cell produces an output signal as shown in FIG. 6b.

This is because the mask of FIG. 6 is translated towards the left to a position where the light source is in perspective relation to the object through part 19.

The preferred light source is a long filament placed parallel to the side edges of the mask 56 or the aforementioned masks.

Figure 6c shows the arrangement of filled and empty cells in the lower half of the mask 56, and Figure 6d shows the arrangement initially in perspective through the partial molecule 20 with respect to the light source 20, and finally on the left side. 3 shows the output signal of a photovoltaic cell receiving energy from an object in perspective relationship through the partial molecule 31 with respect to the light source 20 due to mask translation to .

FIG. 6e receives energy from an object that is initially in a perspective relationship with the light source 20 through the partial molecule 24, and finally becomes in a perspective relationship with the light source 20 through the partial molecule 31 by translation of the mask to the left. Shows the output signal of the photovoltaic cell.

3, 5 and 6, the cell defined by sub-molecules 8 and T9 is shown as A in FIG. 3 during translation of the mask 56 to the left from the solid line position of the mask support element in FIG. Radiates only in the indicated area.

Similarly, the cell defined by submolecules 9 and T10 radiates only into regions B and A of FIG. 3 during such mask translation.

An object illuminated in area A causes the photocell to generate the signal of Figure 6b.

This signal is uniquely characterized by an initial 4-bit representation of 0000.

An object illuminated with irradiation B in region B gives an initial 4-bit output of the photocell of 0001.

Such 4-bit patterns are associated with the first two symbols shown on the left side of the table of FIG.

Such encoding of mask 56 results in region A of FIG.
The object illuminated at each of ~N can be uniquely determined by examining the first four bits of the photovoltaic output signal.

Therefore, it is possible to determine in which region of regions A to N an object is present by which photovoltaic cells are energized in the illustrative orthogonal photovoltaic array device of FIG. Information about the area can be identified without having to determine it by checking whether the area is the same.

Therefore, only a single photovoltaic cell needs to be used with a spherical lens that focuses all of the incident energy reflected from areas AN.

On the other hand, the use of photovoltaic matrices serves another purpose,
That is, this is desirable in order to make it easier to examine reflections from a plurality of objects that cannot be easily identified by measurement using the filter shown in FIG.

In this case, a number of photovoltaic cells are used, each capable of detecting reflections from separate objects.

The photovoltaic output signal for the object area identified as described above is then examined for repetition rate to obtain distance information regarding the object reflecting energy.

One type of device implementation for this purpose is shown as a block diagram in FIG.

Scanning detector 58, which may be a shaft encoder with a mechanism for translating mask 56, provides an output representation of lines 60 and 62 at the beginning and end of mask translation, respectively.

Circuit 64 processes these signals and applies output signals on lines 66 and 68 to scanning reflected energy collectors 70a-70n, as described below.

One such collection device is attached to each photovoltaic cell.

The signal on line 66 clears the previous contents of the collector and the signal on line 68 identifies the preselected time for collector signal processing.

The operation of the collection devices 70a-70n is further controlled by the central processing unit 72 directly through the collection device selection lines 74, 76, 78.
and 80 and further controlled through read controller 82 .

82 is connected to device 72 by data transfer control lines 84, 86 and 88 and to collection devices 70a-70n by line 90.

The collection devices 70a to 70n transmit the collected information to lines 92.9.
4, 96, 98 and 100 (input data bus) to central processing unit 72.

Device 72 sequentially sends signals to collection device selection lines 74, 76, 78 and 80.

These signals have address components representing each of the collection devices 70a-70n.

If such address is that of collection device 70a, collection device 70a is activated by the signal on line 90 and sends the collected information to device 72 on lines 92, 94, 96, 98, and 100.

As discussed in more detail below, line 92 provides an output signal when no reflected energy is being collected;
Device 72 can then proceed immediately to the next collection device.

When reflected energy is being collected, input data bus lines 94, 96, 98 and 100 provide signals indicating the time interval between such reflected energy.

Upon receiving such time interval information, device 72 operates to calculate the X distance of the object.

In the more detailed block diagram of FIG. 8, an example of the photovoltaic output signal is shown in the upper left corner.

This signal also exhibits inherent noise between peaks indicating reflections from objects.

The first function of collector 70a is to distinguish between photovoltaic output signals that exhibit reflected energy components and photovoltaic output signals that consist only of noise.

The output of photovoltaic cell PC1 is connected to amplifier 10 through line 102.
4 and the output of 104 is simultaneously added to the clock delay circuit 10.
6 and is added to the peak detection device 108.

Peak detector 108 is cleared by the line 66 ON (first preselected voltage level) signal prior to receiving the output of amplifier 104 at the beginning of the scan.

The amplitude of the output of the amplifier is then received and outputs the peak voltage level of that amplitude on line 110.

Divider 112 has a wiper set at about 50% of the peak and about 50% of the peak is applied to diode 114 .

Diode 116 is connected to the power supply of reference voltage V and sets the threshold value.

Processed signals below the threshold are considered to be noise.

When the divider wiper voltage level exceeds this threshold, line 118 is at the divider voltage level.

The comparator 120 has an input resistor 122 and a hysteresis resistor 12.
4, and the former supplies the output of the delay circuit 106 to the comparator.

The output voltage level of delay circuit 106 is
Comparator 120 provides an on signal to AND gate 126 when the voltage level on line 118 is exceeded by an amount equal to the hysteresis feedback voltage set by V.4.

With delay circuit 106 acting as an analog feed register or extended delay line, the output of amplifier 104 is efficiently examined by peak detection device 108 and comparator 120.
allows the line 118 input to to be properly set efficiently by the amplified photovoltaic output prior to reception by the comparator.

During this circuit adjustment time, AND gate 126 keeps one of its outputs off (second preset voltage level) via line 68.

To this end, circuit 64 includes an OR gate 128 having inputs from lines 60 (scan start) and 62 (scan end) and an output connected through a delay circuit 130 to a flip-flop 132. .

Flip-flop 132 is set and reset by sequential pulses on line 134, and when a scan start signal arrives on line 60, inverter 1
36 directly.

This signal also passes through line 66 and also clears peak detector 108, as previously described.

Accordingly, line 68 is set off by resetting flip-flop 132 by inverter 136, and is set on by initializing flip-flop 132 after completion of operation of delay circuit 130.

This state on line 68 continues until line 134 applies the end of scan signal on line 62 to flip-flop 132.

Line 68 is therefore turned on for a time equal to the scan time, but delayed by the circuit adjustment time.

These states are shown in the timing diagram of FIG.

a is a scan start signal, b is a scan end signal, c is a scan time, and d is a scan time delayed by the delay circuit 106.

When input line 68 to AND gate 126 is turned on, the output of gate 126 is selectively turned on in response to the peak of the photovoltaic output signal, and flip-flop 138 is clocked by its clock pulse CP input signal. hand,
As shown schematically in FIG. 9 from e to h, the line 140
Generate a pulse train on top.

It has an initial 4-bit pattern 0000 corresponding to the object in region A of the pulse train H1 in e of FIG.

The pulse train at f of FIG. 9 has an initial 4-bit pattern 1110 that corresponds to the object in region E of FIG.

The pulse train at g in FIG. 9 shows an initial 4-bit pattern 0100 corresponding to the object in area N in FIG.

The pulse train at h in FIG. 9 shows the initial 4-bit pattern 0000, as does the pulse train at e, but is compressed in time and therefore represents an object in region A closer to the reference position R. ing.

The pulse train on line 140 is applied to a monostable multivibrator 142, which applies its output pulses to an OR gate 144.

When the output of OR gate 144 falls, counter 146 is cleared by the input through monostable multivibrator 302 from line 148.

The output of the counter on lines 146a-146n is gated by the clock signal on line 152 at the rising edge and input to storage 150.

Counter 146 is incremented by clock pulses CP applied from line 154 and continuously counts such lock pulses between two consecutive clear operations.

Therefore, the states of lines 146a-146n indicate the time interval between two successive rising edges of the output of OR gate 144.

Writing information into storage device 150 is enabled by line 156 when line 68 is on.

When the output of OR gate 144 falls, line 158 increments address counter 160, and lines 160a-16
Outputs an indication of a different storage position signal on 0d.

The counting direction of the address counter is on lines 68 and 15.
If an on signal is applied to flip-flop 132 by 6° 162 and 164, it is set to increase.

An off signal on line 164 sets the counter to decrement.

Counter 160 is enabled for counting operation when line 166 is ON.

OR gate 168 turns on line 166 during scanning (line 162 is on) and during storage read (line 170 is on).

Line 170 is on when all inputs to AND gate 172 are on.

To examine this input condition, each of the scanning reflected energy collectors 70a-70n is connected to lines 74.76.
It has its own decoder circuit that responds to the 78 and 80 states.

In the case of collection device 70a of FIG.
4, lines 74, 76 and 78 are AND
Connected directly to gate 172.

After gating the signals to the storage device 150, the central processing unit 72, through the operation of the read control unit 82, sequentially polls the acquisition device using the signals on lines 74-80.

In response to device 72 setting flip-flop 176 by sending an ON signal on line 88, monostable multivibrator 178 immediately turns on line 90 through amplifier 180.

Then, when storage device 150 is also given an on input on line 170a (data output enable), address counter 160 is decremented to recall a storage location in storage device 150, and the stored information is transferred from line 94 to 1
00 to device 72.

When the output of monostable multivibrator 178 falls, line 182 sets flip-flop 184 and line 86 turns on, indicating to device 72 that the time setting of monostable multivibrator 178 is complete.

This time is selected such that reading from one storage location of storage device 150 can be completed.

Device 72 examines the data bus line and then connects line 84.
turns on to reset flip-flops 176 and 184, and then begins the next read by turning line 88 on again.

Line 90 is turned on again and the contents of the next storage location in storage device 150 are output on lines 94-100.

This cycle continues until line 92 is turned on,
Inform device 72 that counter 160 has been fully decremented.

As can be readily seen, if no energy is reflected from the object onto the photocell of the collection device 70a, the counter 16
0 is not incremented during scan time.

In this case, line 92 is turned on at the beginning of polling the collector 70a and the device 72 immediately proceeds to poll the next scanning reflected energy collector.

Counter 160 is initialized by line 301 through line 60 at the beginning of the scan.

As previously mentioned, the signals sent to the device 72 by lines 94-100 are the contents between the resets of the counter 146, i.e. the clock between two successive outputs from the photovoltaic cell in response to object reflected energy. is the number of pulses CP.

In the case of the pulse train shown in FIG. 9e, the device 72 receives counts of the order of two values CP1 and CP2.

These correspond to empty and filled cells, respectively.

By selecting the larger CP1 of these two measurements, the device 72 efficiently sorts out the coded portion from the received signal, and then by averaging a large number of CP1 measurements, the device 72 Calculate distance.

h in FIG. 9 shows a train of reflected energy pulses from an object having a smaller X distance from the reference position;
3 and CF2 are derived.

The device 72 selects the larger of these two as the X distance indicator.

As can be seen from FIG. 9, CF2 is smaller than CPl, which means that it is for an object with a smaller X distance.

Identification of the region is made by observing the initial four pits of the signal by a computing device which serves to remove the encoded information to obtain the X-distance information.

In the embodiment shown in FIG. 10, a signal indicating decoded X-distance information and a signal indicating area identification information are generated separately.

Here, the optically transparent encoded portion of the mask 56 in FIG. 6 is eliminated, and the remaining optically transparent portion has a width different from that of the other portions, as shown in FIG. 10a.
Use 6.

In the mask 56, the cells have adjacent optically transparent portions, e.g.
8'-T9'.

A cell is considered to be "empty" if the left side of the adjacent light-transmissive parts defining the cell has a width W1.

For example, the cell defined by T8'-T9' is empty.

Similarly, if the left side light-transmissive portion has a larger width W2, it is considered to be "full."

For example, the cell defined by adjacent light-transmissive moieties 12' and T13' is full.

In FIG. 10a, it can be seen that the initial four cells starting from T8' are empty and 0, the next three cells are full and 1, and so on.

The encoding pattern of the mask 56 is the same in terms of the upper and lower encoding cells of the mask 56 and their connections, and the sixth
Defined in figures a-6d.

In FIG. 10, photovoltaic cell PC outputs its output signal on line 186.

FIG. 11 shows such a signal with a coding pattern 11001.

This signal is amplified by amplifier 187 and sample gate 188
added to.

Gate 188 is enabled to pass such signals when line 189 is on.

This state is applied at the beginning of each scan.

This is because flip-flop 190 is reset by the reset signal on line 305 through inverter 191 at the end of the previous decoding cycle.

When gate 188 opens, the amplified photovoltaic signal passes through signal mixing circuit 192 to delay circuit 19
Added to 3.

At this time, the scan start signal on line 60 is transmitted to inverter 19.
4 is added to the delay circuit 193, so the delay circuit 1
93 is in a cleared state.

In the case described above with respect to FIG. 8, 50% of the peak value detected by peak detector 195 (which is then cleared by the scan start signal) is provided by divider 196 and connected to diodes 197 and 198. is applied to comparator 200 through line 199.

Comparator 200 has hysteresis resistors 201 and 202 that turn on line 203 when the output of delay circuit 193 exceeds the voltage level on line 199.

Inverter 194 sets flip-flop 204 at the beginning of each scan.

In this way, line 205 of flip-flop 204
is turned off, the clock pulse from the clock generator 206 is sent to the preset counter (delay circuit 207).
can be decremented or incremented, and then the pulses separated by the amount of time delay of delay circuit 193 are sent to line 208.
is output to.

The first such pulse occurs after loading of the delay line and peak detection device, as shown in FIG.

Inverter 209 inverts the signal on line 208, thereby passing through line 210 to flip-flop 19.
0 is set.

The sample gate 188 is then disabled;
Further input of the photovoltaic output to the delay circuit 193 is suppressed.

Delay circuit 193 then acts as a recirculating loop including line 211.

When flip-flop 190 is set as described above, line 221 to the AND gate is turned on, creating an output path from comparator 200 to line 223.

Line 223 triggers monostable multivibrator 224 and its output signal is processed in phase-locked loop 225 as described below.

The loop 225 includes a control flip-flop 226, a voltage controlled oscillator VCO 227, a sample gate 228, and an integrator 22.
9 and a filter 230.

During the loading of the delay circuit and peak detection device, the output line 231 of the flip-flop 226 is kept off due to the reset of the flip-flop 226 that occurs at the end of the preceding scan, and the signal on such preceding line 305 is Inverter 191.232. OR gate 233
and flip-flop 22 through inverter 303
6 is input.

Flip-flop 226 connects inverter 304 when monostable multivibrator 224 turns on line 234.
is set by , then the voltage controlled oscillator 227 becomes
It operates at a frequency set to match the pulse output rate of monostable multivibrator 224, as sampled by gate 228.

Such frequency setting of voltage controlled oscillator 227 is 22
7 by a pulsed output signal on line 235.

When delay circuit 207 sends a pulse on line 208, flip-flop 226 is reset by OR gate 233 and inverter 303.

The recirculated photovoltaic output signal is output to line 22 by comparator 200.
3, flip-flop 226 is set again, and then phase-locked loop 225
The oscillator 22 repeats its operation in response to the recycled information.
7 frequency settings are executed sequentially.

The signal on line 235, which is indicative of the setting of oscillator 227, is squared by squaring circuit 236 and applied to line 237 as the clock for send register 238.

The output of AND gate 222 is connected to the line 237 signal (first
A clock is input into the send register 238 at the falling edge of FIG.

At this time, whether it is 1 or 0 is determined based on the pulse width of the line 223 signal.

For the typical photovoltaic output signal shown in FIG. 11, the conditions shown schematically with respect to line 239 at the input flip-flop of send register 238 are shown.

In this case, the code 11001 is shown.

In response to a change in the state of flip-flop 226, line 240 transfers the signal from send register 238 to latch circuit 2.
41, and this circuit allows these signals to be output as digital words on output line 242.

To provide a direct indication of the X distance, the apparatus of FIG. 10 applies the output signal of monostable multivibrator 224 to AND gate 243 and enables gate 243 with the output of flip-flop 226.

A burst of pulses on line 234 is applied to a frequency-to-voltage converter 244 when line 231 is on, and the voltage output of 244 is applied to the sample and hold circuit 244.
5 and is input to a voltmeter 246 having a distance scale.

The enable signal for sample and hold circuit 245 is
produced by a monostable multivibrator 306, 3
06 outputs a signal when the output of the AND gate 243 rises.

The reset signal on line 305 may be delayed at the discretion of the user of the apparatus of FIG. 10 to allow for multiple recirculation as shown in FIG. 11.

In that case, the readout for the word on line 242 can be observed for a settling time, and the last value of the repeated readout can be used to confirm the previous readout.

The present invention also allows for simplified implementation.

In that case, the oscilloscope can be used to directly display the photovoltaic output output from amplifier 187 or to display the photovoltaic output processed onto line 223.

In the former case, the output of amplifier 187 is preferably observed with a memory scope when triggered by the scan start signal on line 60.

In the latter case, the repeated line 223 signal is sent to gate 2
33 can be shown on a conventional oscilloscope when triggered.

The oscilloscope allows to demonstrate the encoding based on the different pulse widths being displayed and the X-distance based on the time interval between the pulse rising edges.

As can be readily seen, the apparatus of Figures 7, 8 and 10 includes:
It can also be used to process reflected energy from objects illuminated by non-coded radiant energy patterns.

In that case, since the device 72 of FIGS. 7 and 8 averages all the received counts, there is no need to use a function to determine whether the counts are large or small.

When the apparatus of FIG. 10 is used with non-coded patterns, the code detection circuit can be omitted.

As previously mentioned, the photovoltaic array device 26 can be used for the purpose of practicing the present invention using a non-coded radiant energy pattern, or from a different object when using a coded radiant energy pattern, as shown in FIG. can be configured for the purpose of separating reflected energy.

As also mentioned above, the photovoltaic array can be constructed with a single photovoltaic cell if the radiant energy pattern used is encoded in both the Y and two directions of FIG. 3.

Figure 12a shows an optical configuration that allows the use of yet another photovoltaic array.

The photovoltaic array device 26' of FIG. 12a is 26'a. 26
It consists of three rows, 26'b and 26'c, and six columns, 26'd.

When using the entire photovoltaic array 26', the object O7
The reflected energy from an object observed by a single spherical lens 214 spans the entire width of the photovoltaic array in the lateral and vertical directions, as shown by the solid lateral contour and the solid and dashed vertical contours. It will be incident.

Such a vertical profile can also be compressed so that the reflected energy is incident only on the photovoltaic array 26b, such as the reflected energy incident range shown in solid lines.

In that case, for example, the spherical lens 214 and the cylindrical lens 21
6 (biconvex) and 218 (biconcave) is used.

FIG. 12b is a plan view showing that the object reflected image is not compressed in the horizontal direction, and FIG. 12c is a side view showing that the object reflected image is compressed in the vertical direction.

Mask 220 of Figure 13 can be used with the optical arrangement of Figure 12a.

This mask provides an encoded radiant energy pattern in the transverse direction, ie, along the y-axis of FIG.

The same reference numerals are used as shown in the top half of mask 56 in FIG. 6, but in mask 220 adjacent transparent portions are separated by an array of empty or filled cells of uniform width. The code is defined such that 0 is defined when the distance is D1, and 1 is defined when the distance is D2.

Here, Dl and D2 are different.

For clarity, FIG. 6a is repeated in FIG. 13a under mask 220 to illustrate such cell encoding.

If the mask is encoded with a sending code and the total number of first cells (empty or short) and second cells (full or long) in the chain of cells, then Each segmental string of cells represents a distinguishable string of first cells and second cells.

The relationship between P and N is shown by the equation 2N-1=P.

It is of course possible to use a different encoding than the one using the sending code, but the number of divisions required to identify one cell must be increased.

For example, the structure of the mask may be encoded such that the first and second cell chains in the cell chain are pure binary representations.

It will be apparent to those skilled in the art that various changes and modifications to the embodiments described above may be made without departing from the spirit and scope of the invention.

For example, the present invention contemplates measurements of not only the aforementioned translations of the light source and mask combination, but also other movements of the radiant energy pattern.

Accordingly, the foregoing is merely illustrative of the invention and should not be construed as limiting.

[Brief explanation of drawings]

The attached drawings show an embodiment of the present invention, and FIG. 1 is a front view of the device, and FIG.
1 is a partial cross-section of the device shown in FIG.
2a and 2b are schematic cross-sectional views of the device in FIG. 1 along the line ■-■ in the figure, and FIGS. 2a and 2b are schematic diagrams of non-encoding masks having a structure different from the non-encoding masks in FIGS. 1 and 2, 3 shows an object in the field of view of the photovoltaic array device of FIG. 1, FIG. 4 is a block diagram schematically showing the photovoltaic array device of FIG. 1 together with an electrical processing circuit, and FIG.
The figure shows a code generation circuit and a code explanation cloth, and FIG. 6 is a front view of a mask structure used for the code in FIG.
FIG. 6a is a schematic diagram illustrating the sequence of signals in FIG. 6b, and FIG. 6b is a sequence of signals corresponding to the reflected radiation energy from an object irradiated by the upper half of the mask in FIG. Figure 6c is a chain of signals corresponding to the reflected radiation energy from the object irradiated by 1 onto the lower half of the mask in Figure 6, and Figure 6d is a schematic diagram explaining the chain of signals in Figure 6c. 6e is another signal chain formed by the use of the mask of FIG. 6, FIG. 7 is a general block diagram of an apparatus for processing the generated signals, and FIG. 7 is a detailed block diagram of the device shown in FIG. 7, FIG. 9 is a timing diagram for explaining the operation of the device shown in FIG. 8, and FIG. 10 is a detailed block diagram of the device shown in FIG. 10a is a front view of another mask structure that implements the symbol of FIG. 5, and FIG. 11 is a timing diagram for explaining the operation of the apparatus of FIG. 10. , 12a.
12c is a uniaxial optical arrangement for use with a photovoltaic array cell, and FIG. 13 is a front view of another encoded mask structure. In the figure, 10 is a position measuring device, 16, 16', 16'' are non-coded masks, 56, 56', 220 are coded masks,
18 is a drive disk, 20 is a light source, 20a is a lamp, 2
6, 26' are photovoltaic array devices, 26'a, 26'b, 2
6'c is a horizontal row of photocell arrays, 26'd is a column of photovoltaic arrays, 26a, 214°, 216.218 are lenses, 50 is a code generation circuit, 70a to 70n are reflected energy collectors, 72 is a central processing unit, and PC1 ~PCl4 is a photovoltaic cell,
T1-T7. T', T8-T19. T20~T31゜T
8', T9' are optically transparent or semi-transparent parts of the mask, NT1 to NT6. NT1 is the opacity of the mask or T1
~T7. A portion having a transparency different from T'1, V is a space, T is a translation axis, Po is a reference plane, R is a reference position, P1.
P2. P3. P'1. P1″ is a plane parallel to T, P1−
1. P1-3. P1-5. P1-7. P1-9. P1-
11. P1-13 is the first region on plane P1, P1-2
．． P1-4. R1-6, P1-8. P1-10. P1-
12 is a second region on plane P1, P2-1 is a first region on plane P2, P2-2 is a second region on plane P2, P
3-1 is the first area on plane P3, P3-2 is plane P3
Upper second region, Ol, O2, O3, O4 ° O5, O6
is a radiant energy reflecting object, X1. X2°X3 is the distance from R of the object in the direction perpendicular to the axis T in the horizontal plane, Y1. Y2
．． Y3 is the distance from R of the object in the direction of axis T, Z1. Z2. Z
3 is the vertical distance from R, TE1 to TE5. TE6~
TE9 is the encoding portion of the mask 56.

Claims (1)

Claims: 1 (a) propagating a divergent radiant energy pattern having different adjacent pattern portions; (b) propagating the divergent radiant energy pattern such that the adjacent pattern portions are sequentially incident on a radiant energy reflecting object; (c) generating an output signal indicative of a change in the radiant energy so collected as a function of time; A method for obtaining information about the position of a characteristic radiant energy reflecting object. 2. A claim in which the adjacent pattern portions each contain a different intensity of radiant energy, and wherein step (c) is carried out by generating the output signal as an indicator of a change in intensity of the collected radiant energy as a function of time. The method described in item 1 of the scope. 3. The method of claim 1, wherein said step is carried out in part by translating said radiant energy pattern along a preselected axis. 4. Step (e) comprises forming the radiant energy pattern in such a way that the adjacent pattern portions each contain different intensities of radiant energy, and the portions have equal widths along straight lines on a plane parallel to the preselected axis. 4. A method as claimed in claim 3, wherein the method is carried out by propagating incident to adjacent areas. 5. The method of claim 4, wherein step (c) is performed by generating the output signal as an indicator of the repetition rate of intensity changes of the collected radiant energy. 6 carrying out step (b) in part by defining a plurality of energy collection locations at the common location disposed along a first axis consisting of the translational axis or an axis parallel to the translational axis; 6. The method of claim 5, including the further step of generating another output signal indicative of the energy collection location at which the radiant energy reflected by the object is incident. 7 said step (b) is carried out at said common position disposed along a first axis consisting of said translational axis or an axis parallel to said translational axis and along a second axis transverse to said first axis; Claim 1 carried out in part by defining a plurality of energy collection locations and including another step of generating another output signal that is indicative of the energy collection location on which the radiant energy reflected by the object is incident. The method described in Section 5. 8 carrying out step (b) in part by defining a plurality of radiant energy collection locations at the common location;
9. The method of claim 1, further comprising the step of generating another output signal indicative of the energy collection location at which the radiant energy reflected by the object is incident. and arranged in a matrix along a second axis, and generating said another output signal as an indication of the relationship between said energy collection location at which radiant energy reflected by an object is incident and said first and second axes. 9. The method according to claim 8. 10 another step of encoding the radiant energy pattern in the direction of the movement of the pattern in step (b) and producing another output signal that is indicative of the encoding indicated by the collected radiant energy; A method according to claim 1 comprising: 11. The method of claim 10, wherein the radiant energy pattern is also encoded in a direction transverse to the direction of movement of the pattern. 12. A method of using a radiant energy source to obtain information about the position of an object in a space with respect to a reference position in the space, comprising: (a) translating the radiant energy source along an axis in the space. (b) while so translating the energy source, selectively emitting radiation from the energy source in a divergent manner into the space such that a plane in the space parallel to the axis is a first plane; irradiated over a region, the first region being separated from each other by a second region receiving a different irradiation than the first region, and each of the first region and the second region being in a straight line. (e) collecting at said reference position the radiant energy reflected by said object to said reference position; and (d) the repetition rate of the radiant energy so collected. A method comprising the step of generating an output signal that is an indicator of. 13. The radiant energy is optical energy, and step (b) is carried out by placing a mask between the object and the energy source and translating the mask together with the energy source. The method according to scope item 12. 14 carrying out step (c) in such a way that the position of the collected radiant energy incident at the reference location is detected along and transversely to the axis, and an indicator of the position of such incident is detected; 13. A method as claimed in claim 12, including the further step of generating another signal. 15 (a) a pattern generation device for propagating a divergent radiant energy pattern having different adjacent pattern portions; (b) a drive device for moving the pattern generation device relative to an object reflecting radiant energy; a collection device fixedly disposed relative to the object for collecting radiant energy and producing a signal indicative of the reflected energy;
and (d) obtaining information regarding the position of a radiant energy reflecting object, comprising a signal processing device for producing an output signal that is indicative of the time interval between successive signals of the signals produced by the collecting device. Device. 16. The apparatus of claim 15, wherein the pattern generating device comprises a radiant energy source and a radiant energy mask supported for movement therewith. 17. The apparatus of claim 15, wherein the pattern generation device propagates the divergent radiant energy pattern encoded in the direction of movement of the pattern generation device by the drive device. 18. The apparatus of claim 15, wherein the pattern generation device propagates the divergent radiant energy pattern encoded in a direction transverse to the direction of movement of the pattern generation device by the drive device. 19. Claim 15, wherein the pattern generating device propagates the divergent radiant energy pattern that is encoded both in the direction of movement of the pattern generating device by the drive device and in a direction transverse to the direction of movement of the pattern generating device. The device described in. 20. The apparatus of claim 15, wherein the signal processing device generates another output signal that is indicative of the encoding content of the signal generated by the acquisition device. 21. The apparatus of claim 19, wherein the signal processing device generates another output signal that is indicative of the encoding content of the signal generated by the acquisition device. 22. Claims in which the collecting device comprises a radiant energy sensitive device for producing an electrical signal indicative of changes in incident radiant energy and a lens device for collecting the radiant energy reflected by the object. 1st
The device according to item 5. 23. The apparatus of claim 22, wherein the device sensitive to radiant energy comprises a plurality of detectors arranged along the direction in which the pattern generating device is moved by the drive device. 24. The device sensitive to radiant energy comprises a plurality of detectors arranged in and transversely to the direction in which the pattern generating device is moved by the drive device. equipment.