JP3316223B2 - Color detection device with edge processing function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention illuminates an object to be detected,
The present invention relates to a color detection device which detects the characteristic of an object to be detected, for example, a color by analyzing the reflected light or transmitted light, and particularly relates to a device which has an edge processing function to improve detection accuracy.

[0002]

2. Description of the Related Art Conventionally, as a color detecting device for optically detecting a color, for example, a light source for projecting light irradiates an object to be detected, and a light receiving means such as a photodiode or the like which reflects light or transmitted light from a light receiving spot. And the output signal of the light receiving means is analyzed to determine the color of the detected object from the aspect of hue, saturation, and the like.

[0003]

According to such a color detection device, not only an object to be detected but also an object adjacent to the object may be caught by a light receiving spot. Since a signal is output from the light receiving unit based on reflected light or transmitted light from both the object and the adjacent object, the color of the detected object is erroneously detected.

Therefore, conventionally, a boundary detecting device is provided separately from the light receiving means, and it is detected by the boundary detecting device whether or not the light receiving spot protrudes from the contour of the object to be detected. However, measures have been taken to effectively handle the output signal of the light receiving means only during the output of the synchronization signal.

However, in such a case, it is necessary to separately provide a sensor for boundary determination or the like, which is costly. In addition, synchronous control cannot be performed unless the area monitored by the boundary determination sensor coincides with a light receiving spot specified retrospectively from the light receiving device. However, since the boundary determination sensor and the like are installed separately from the light receiving means, this adjustment is performed. The task is very difficult, and it is virtually impossible to completely match the monitoring area to the light receiving spot. Such a problem can occur not only with a color detection device that optically detects a color as described above, but also with a color detection device that optically detects the state of an object having an outline. .

The present invention has been made in view of such a point. The object of the present invention is to divide a light receiving spot into a plurality of spots and to color the reflected light or transmitted light from each divided area. Independent analysis is performed to detect that the received light spot does not protrude from the contour of the detected object through the matching of these colors, so that low cost and no complicated adjustment work are required, and false detection is performed. It is an object of the present invention to provide a color detection device that can surely prevent the color detection.

By the way, the light receiving means outputs the output voltages VR, VR according to the intensities of the three elements of light, red, green, and blue.
Generally, a method of generating VG and VB is used. As a method of analyzing a color from the output voltage, for example, determination constants Vx (= VR / VG) and Vy (= VB / VG) are derived, and this Vx It is conceivable to analyze the color by referring to a two-dimensional map based on Vy and Vy. In this way, even if the output voltages VR, VG, VB fluctuate due to distance, temperature, disturbance light, and other factors,
In the determination constants Vx and Vy, the fluctuations are canceled by the numerator and the denominator, so that the influence of the fluctuations can be canceled and the color analysis can be stably performed.

However, in this case, when the voltage value of the denominator of the judgment constant is small and substantially "0", Vx and Vy diverge to infinity, and both the voltage values of the denominator and the numerator are substantially "0". Occasionally, Vx and Vy become indefinite values, color analysis cannot be performed stably, and detection accuracy is poor.

It is another object of the present invention to stably perform color determination by deriving a determination constant indicating a substantially determined value for any reflected light or transmitted light and performing color analysis. I have to.

[0010]

According to a first aspect of the present invention, there is provided a color detecting apparatus having an edge processing function for each of a plurality of divided areas obtained by dividing a light receiving spot. A light receiving means 14 for receiving light from the divided area and outputting a detection signal for each light element;
4, a variable calculating means 30 for calculating a determination constant based on the detection signal, an area storage means 40 for storing the correspondence between the determination constant and the color, and a variable calculating means 3
A color determining means for receiving a 0 output and outputting a color signal specifying a color based on a determination constant while referring to the area storage means; Then, the validity judging means 60 which receives the output of each color judging means 50 and outputs a coincidence signal when each color signal coincides is provided. Here, the light is a concept including reflected light, transmitted light, and the like. Sa
Further, as shown in FIG. 4, the light receiving means changes the light intensity to red,
Multiple color-capable photo die that detect each blue and green element
Aether 14, which is located at the detection part
Into a bundle of light-receiving fibers 23 whose entrance surface is divided into a plurality.
Each exit surface is branched, and each exit surface at the branch end is
The photodiode 14 is opposed to the photodiode 14.

According to a second aspect of the present invention, there is provided a color detecting apparatus with an edge processing function, wherein the variable calculating means includes a first denominator of a sum of primary terms of a detected signal and a numerator of one detected signal. It is configured to output two or more decision constants each consisting of a fraction to be processed. Here, the primary term of the detection signal is a number obtained by multiplying the detection signal by a constant (including 1). Therefore, the sum of the primary terms of the detection signal is obtained by calculating this for a plurality of detection signals. It is the sum of

[0012]

According to the first aspect of the present invention, the reflected light or transmitted light from each divided area of the light receiving spot enters the corresponding light receiving means, and the variable calculation means 30 calculates the determination constant, and the color determination means 50 Outputs a color signal. That is,
Each incident surface of the light receiving fiber 23 in which the incident surface is divided into a plurality
The incoming light is branched for each incident surface, and each photodiode 1
4 and is subjected to arithmetic processing.

As long as the light receiving spot captures only the detected object, the color of the object captured in each divided area is the same. Therefore, the color signals output from the respective color determination means 50 match, and the validity determination means 60 Outputs a match signal. On the other hand, if the light receiving spot captures not only the object to be detected but also an object adjacent thereto, the color of the target captured in each divided region differs. Therefore, the color output from each color determination unit 50 according to this difference. The signals are shifted at random, and no coincidence signal is output from the validity determination means 60. Therefore, if color detection is executed by effectively handling the color signal only when a coincidence signal is received, erroneous detection is prevented.

In this case, for example, it is conceivable that it is determined that the light receiving spot captures only the object to be detected based on the same amount of reflected light from each divided area. However, depending on the color, even if the reflected light amount is the same, the detection signal may be different, and erroneous detection cannot be avoided. In this regard, in the first aspect of the present invention, the above-described determination is made based on the identity of the finally obtained color signals, so that there is no erroneous detection.

Further, when the light reflected or transmitted from the divided area is introduced into the light receiving means 14 through an optical fiber, each detection signal fluctuates when the optical fiber is replaced. Since the area storage means 40 and the color judgment means 50 are provided, adjustment or resetting of the area storage means 40 after the replacement of the optical fiber absorbs fluctuations of each detection signal and maintains detection accuracy.

According to the second aspect of the present invention, each determination constant is
Since the sum of the primary terms of the detection signal is a denominator and one detection signal is a numerator, even if the detection signal fluctuates due to distance, temperature, disturbance light, and other factors, the numerator and denominator are determined by the determination constant. , The fluctuation is canceled out, so that the influence of the fluctuation can be canceled and the color analysis can be stably performed.

In addition, since the denominator is the sum of two or more detection signals, the determination constant does not diverge or become indefinite even if one of the detection signals becomes substantially "0". Accordingly, the determination constant indicates a value almost determined for any reflected light.

[0018]

Embodiments of the present invention will be described below. This embodiment is a color detection device having a function of detecting light intensity for each of red, blue, and green components. This color detection device
The device body 10 and the detection unit 20 are provided. The detection unit 20 is provided to the object T to be detected, and the position of the object T is adjusted or the color of the object T is adjusted by appropriately operating the device body 10. It is to detect optically.

First, FIGS. 2 and 3 show a box-shaped apparatus main body 10.
An electronic circuit (not shown) for controlling light projection or processing a signal obtained from reflected light, transmitted light, or the like is accommodated in a lower portion inside the same. 11 is a cylindrical connector socket integrally formed on the side wall of the apparatus body 10, 12 is a halogen lamp fixed inside the apparatus body 10 so as to face the connector port 11, and 13 is a relay fiber made of an optical fiber. And one end thereof is opposed to the irradiation surface of the halogen lamp 12 and the other end is a connector receiving port 11.
It is fixed by penetrating the center of the inner side wall. A pair of first and second photodiodes 14 and 14 as light receiving means are fixed to the left and right of the relay fiber 13 on the side wall inside the connector port 11 with their light receiving surfaces facing outward. . The first and second photodiodes 14,
Reference numeral 14 denotes a color-compatible photodiode that detects light intensity for each of red, blue, and green components. Reference numeral 17 denotes a power cord connected to the electronic circuit and the like.

FIG. 4 shows the detector 20. In the figure, 2
Reference numeral 1 denotes a head provided to the object T to be detected, and a light projecting fiber 22 and a light receiving fiber 23 are connected to the head 21. A light receiving lens 24 is fixed at one end in the head 21 at the center, and a pair of light projecting lenses 25 having optical axes intersecting on the optical axis of the light receiving lens 24 are fixed to both sides thereof. In the head 21, the light projecting fiber 22 is branched into two beams, and the light emitting surfaces of the branched ends are fixed to the light projecting lens 25 so as to face each other on the optical axis. The incident surface of the light receiving fiber 23 is divided into two equal parts as shown in FIG. 9 so that two half moons meet.
4 is fixed so as to face on the optical axis. In the figure, reference numeral 26 denotes a light transmitting glass.

In FIG. 4, reference numeral 27 denotes a connector. The connector 27 is fitted into the connector receptacle 11 and is fixed to the apparatus main body 10 by a fastening ring 28. The connector 27 has the light emitting fiber 22
And the light receiving fiber 23 are connected, and the light incident surface of the light projecting fiber 22 is fixed to face the light emitting surface of the relay fiber 13. The light-receiving fiber 23 is composed of two bundles of fibers 23a and 23b divided at the incident surface.
, And each of the emission surfaces at the branch ends is fixed to face the first and second photodiodes 14 and 14, respectively.

Next, the above electronic circuit will be described with reference to FIG. For convenience, only the circuit on the first photodiode side (the upper half in the figure) will be described. First photodiode 1
4 is an output voltage vR, depending on the intensity of each element of red, blue, and green.
It has three detectors 14a to 14c that generate vG and vB. The output terminals of the detection units 14a to 14c are connected to three amplifiers 31a to 31c. The above amplifier 3
Between the output terminals 1a and 31b and between the output terminals of the amplifiers 31b and 31c, a resistor having a resistance value of 2r connected in series is inserted. Reference numerals 35 and 36 denote dividers which output a value obtained by dividing the input current of the Y terminal by the input current of the X terminal to the Z terminal as a voltage. The X terminal of the divider 35 is connected to the connection between the resistors 32 and 33 between the output terminals of the amplifiers 31a and 31b, and the Y terminal is connected to the output terminal of the amplifier 31a with a resistance value r.
Are connected via the resistor 34 of the first embodiment. Also, the divider 36
Is connected to a connection between resistors 32 and 33 between output terminals of the amplifiers 31b and 31c, and an output terminal of the amplifier 31c is connected to a Y terminal via a resistor 34 having a resistance value r. ing. Therefore, the output voltages vR, vG, and vB of the detection units 14a to 14c are output from the amplifiers 31a, 31b, and 3 respectively.
The signal is amplified to VR, VG, and VB by 1c. Since the ratio of the resistance values of the resistors 32 to 34 is 2: 2: 1 in the divider 35, “Vxa = 2 · VR / (VR + VG)”
Is calculated, and this Vxa is output to the Z terminal, and the divider 36 similarly calculates “Vya = 2 · VB / (VB
+ VG) ", and this Vya is output to the Z terminal. These resistors 32-34 and dividers 35, 36
Accordingly, the variable calculation means 30 which receives the detection signal of the photodiode (light receiving means) 14 and outputs two or more judgment constants each composed of a fraction having the sum of the primary terms of the detection signal as a denominator and one detection signal as a numerator. are doing. The output voltages of the dividers 35 and 36 are input to the one-chip microcomputer MC. On the other hand, the circuit on the second photodiode side has the same configuration as that on the first photodiode side, and the output from the Z terminal is Vxb instead of Vxa and Vy for identification.
Vyb is used instead of a.

The one-chip microcomputer MC comprises an area storage means 40 and a color determination means 50. The first photodiode-side area storage means 40 stores the correspondence between the determination constants Vxa and Vya and the colors as shown on the left side of FIG. The correspondence between the determination constants Vxb and Vyb and the colors as shown on the right side of FIG. These are two-dimensional maps. For example, in the case of the area storage unit 40 on the first photodiode side, "the color is red when the determination constant Vxa is in the area of x1a to x2a and the determination constant Vya is in the area of y1a to y2a". The area is designated as described above, and each area can be independently rewritten. Further, the color determining means 50 receives the output of the variable calculating means 30 and, with reference to the area storing means 40, the color signal of the first photodiode side based on the determination constants Vxa and Vya. The second photodiode outputs a color signal Sb based on the determination constants Vxb and Vyb.

Reference numeral 60 denotes A as the validity judging means.
The ND circuit receives the color signals Sa and Sb, and outputs a match signal J when the color signals Sa and Sb match. The coincidence signal J is input to a color output unit (not shown). The color output unit receives the color signals Sa and Sb and the coincidence signal J, and upon receiving the coincidence signal J, analyzes the color signals Sa and Sb, thereby converting the color of the object to be detected into the hue, saturation, and the like. And display it.

Next, the operation of the above embodiment will be described. FIG.
As shown in (1), the light of the halogen lamp 12 passes through the relay fiber 13 and the light projecting fiber 22, is collected by the light projecting lens 25, and forms a light projecting spot on the object to be detected.
The reflected light or transmitted light from the light receiving spot is condensed by the light receiving lens 24, and is received by the light receiving fibers 23a, 23a.
b and the first and second photodiodes 14, 14
And its output signal enters the electronic circuit.

In this case, as shown in FIG.
As long as the light receiving spot R captures only the detection target T, the color of the target captured in each of the divided areas Ra and Rb is the same.
The color signals Sa,
Sb matches, and the validity determination means 60 outputs a match signal J. On the other hand, as shown in (1) and (5) of FIG. 10, when the light receiving spot R captures not only the object to be detected but also an object adjacent thereto, the color of the target captured in each of the divided regions Ra and Rb. Are different from each other, the color signals Sa and Sb output from the respective color determination units 50 and 50 are displaced from each other in accordance with the difference, and the coincidence signal J is not output from the validity determination unit 60. Therefore, erroneous detection is prevented by performing color detection by effectively treating the color signals Sa and Sb only when the match signal J is received.

In this case, for example, it is conceivable that it is determined that the light receiving spot captures only the object to be detected based on the same amount of reflected light from each of the divided areas Ra and Rb. Will be used to make this determination. However, when an object to be detected is actually made by combining various colors, and this is tried, there are at least 5% or more combinations with different detection signals even if the amount of reflected light is the same. Absent. In this regard, in the above-described embodiment, the above-described determination is made based on the identity of the finally obtained color signals Sa and Sb, so that there is no erroneous detection.

In addition, the operation of the optical fiber 2
Although each detection signal fluctuates when 2 and 23 are exchanged, since the divided areas Ra and Rb have the area storage means 40 and the color determination means 50, the area storage means 4 is replaced after the optical fiber is replaced.
By rewriting the map by adjusting or resetting 0, the fluctuation of each detection signal is absorbed, and the detection accuracy is maintained.

Further, since another type of sensor other than the photodiode is not required, the cost can be reduced. In addition, only the position of the head 21 needs to be adjusted for color detection, and operability is good.

Further, in the above embodiment, each determination constant Vx
Since a, Vya or Vxb, Vyb is a fraction with the sum (VR + VG) and (VB + VG) of the primary terms of the detection signal as a denominator and one detection signal VR, VB as a numerator, distance, temperature, disturbance light, Even if the detection signal fluctuates due to other factors, the determination constants Vxa, Vya, Vxb,
Since the variation is canceled by the numerator and denominator of Vyb, the influence of the variation can be canceled and the color analysis can be stably performed.

Moreover, the determination constants Vxa, Vya, Vx
Since the denominator of b and Vyb is the sum of the two output voltages VR and VG or VB and VG of the photodiode 14, even if the intensity of one of the elements is small and the detection signal of that element becomes almost "0", Determination constants Vxa, Vya, Vxb, V
yb does not diverge or become indeterminate. Therefore, the determination constants Vxa, Vy for any reflected light or transmitted light, etc.
The values a, Vxb, and Vyb indicate substantially fixed values, color determination can be performed stably, and detection accuracy can be improved. That is,
As previously proposed, the determination constant Vx is set to “Vx = VR / V
G "and Vy derived by" Vy = VB / VG ", and when performing color determination based on Vx and Vy, the determination constants Vx and Vy tend to diverge or become indeterminate. As shown, the regions of each color in the map are dispersed, and accurate color determination cannot be performed. In contrast,
In the above embodiment, as shown in FIG. 7, the regions of each color in the map are distributed at substantially equal distances without being dispersed, and it is clear that the accuracy of the color determination is greatly improved.

Further, since each photodiode has two determination constants of Vxa and Vya or Vxb and Vyb, the area storage means 40 and the color determination means 50 perform processing based on two-dimensional data, and the processing speed can be increased. The structure of the one-chip microcomputer MC or the like is simplified, and the cost can be reduced.

In the above-described embodiment, an analog circuit and a digital circuit are used in combination. However, whether analog processing or digital processing is performed does not affect the essence of the present invention. Further, the determination constants Vxa and Vya are set to “Vxa = 2 · VR /
(VR + VG) ”and“ Vya = 2 · VB / (VB +
VG) ”, but this is only an example and“ Vxa
= K1 · VR / (K2 · VR + VG) ”and“ Vya =
K3 · VB / (K4 · VB + VG) ”(K1, K2, K
3, K4 are constants). Further, the denominator of the determination constant may be a sum of first-order terms of VR, VG, and VB.
In short, the judgment constant may be a judgment constant consisting of a fraction with the sum of the primary terms of the detection signal of the photodiode 14 as a denominator and one detection signal as a numerator, and the number of judgment constants may be two or more.

The position adjustment of the head 21 is as follows.
As shown in FIG. 4, when the head 21 is moved closer to the detection target, the two light emitting spots E begin to intersect, and the light receiving spot R starts to fall within the overlapping portion of the two light emitting spots E ( A state). When the head 21 is further moved closer to the object to be detected, the two light projecting spots E completely overlap, and the light receiving spot R is contained therein (state B). Further, when the head 21 is moved closer to the detection object,
The two light emitting spots E shift, and the light receiving spot R starts to protrude from the overlapping portion of the two light emitting spots E (state C). It is desirable to adjust the position of the head 21 so that each spot is between these points A to C.

In the above embodiment, the light receiving spot R is equally divided into two parts, Ra and Rb.
Are equally divided into 23a and 23b. Although this configuration is most effective in simplifying the optical system and the signal processing system, it is not always necessary to divide the system equally. Further, in the case of the above embodiment, if (1) to (10) are described with reference to FIG.
Object T and light receiving spot R in the direction along (5)
When the (detection unit 20) is relatively moved, the light receiving spot R
Can determine satisfactorily whether or not only captures the object T to be detected, and in the relative movement in the direction intersecting with this,
There is little difference in colors obtained from the light receiving spots Ra and Rb, and high resolution cannot be expected. Of course, this is not a problem in terms of practicality, but if it is desired to have an omnidirectional type in which the direction of relative movement can be arbitrarily selected, as shown in FIG. What is necessary is just to divide further.

In the above embodiment, the light projection spot is formed by the light from the two light projecting fibers 22, but the light projection spot may be formed by one light source. Further, although the light projecting fiber 22 and the light receiving fiber 23 are used, a light source or the like may be arranged adjacent to the lens without using these.

[0037]

As described above, according to the first aspect of the present invention, there is provided a color detecting apparatus having an edge processing function for each of a plurality of divided areas obtained by dividing a light receiving spot, for each light element from reflected light or transmitted light. , A judgment constant is calculated from the detection signal, a color signal is obtained based on the judgment constant while referring to the correspondence between the existing judgment constant and color, and a match signal is output when each color signal matches. Therefore, if color detection is performed by effectively handling color signals only when a match signal is received,
When the light receiving spot catches not only the object to be detected but also the object adjacent to the object, the color detection is automatically interrupted and erroneous detection can be reliably prevented. A color detector that optically detects the state of an object having a contour, because it eliminates the need for a sensor or the like, thereby reducing costs and eliminating the need for adjustment work for detection, resulting in excellent operability. It is widely available. In this case, it is determined whether or not the light receiving spot captures only the object to be detected based on the identity of the finally obtained color signals. Detection can be greatly reduced. In addition, when the divided area and the light receiving means are optically connected, the fluctuation of each detection signal due to the exchange of the optical fiber can be absorbed by adjusting or resetting the area storage means, so that good detection accuracy can be maintained.

Further, the color detecting apparatus with an edge processing function according to claim 2 outputs two or more judgment constants each consisting of a sum of the primary terms of a detection signal as a denominator and one detection signal as a numerator. Even if the detection signal fluctuates due to temperature, disturbance light, and other factors, the influence of this fluctuation is canceled and the color analysis can be performed stably, and the divergence and uncertainty of the judgment constant are prevented, and any reflected light or transmitted light The determination constant is substantially determined for light and the like, and color determination can be performed stably, thereby improving detection accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of the invention of claim 1;

FIG. 2 is a longitudinal sectional front view of the apparatus main body of the embodiment,

FIG. 3 is a side view of the apparatus main body of the embodiment,

FIG. 4 is an exploded view of a detection unit and a connector according to the embodiment;

FIG. 5 is a perspective view of a main part of a detection unit and an apparatus main body according to the embodiment,

FIG. 6 is a circuit diagram of an electronic circuit according to the embodiment;

FIG. 7 is a pair of map diagrams showing a correspondence relationship between a determination constant and a color according to the embodiment;

FIG. 8 is a pair of map diagrams showing a correspondence relationship between determination constants and colors in a comparative example;

FIG. 9 is an end view showing an incident surface of the light receiving fiber of the embodiment;

FIG. 10 is an explanatory diagram showing a color signal and a coincidence signal according to a light receiving spot position according to the embodiment;

FIG. 11 is a plan view showing a divided area of a light receiving spot according to a modified example.

[Explanation of symbols]

 T Detected object 14 Photodiode (light receiving means) 30 Variable operation means 40 Area storage means 50 Color judgment means 60 Validity judgment means Ra divided area Rb divided area

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-1-185421 (JP, A) JP-A-3-218422 (JP, A) JP-A-55-125417 (JP, A) JP-A-3-185 135740 (JP, A) JP-A-63-249029 (JP, A) JP-A-56-151974 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01J 3 / 00-3 / 52 G01N 21/00-21/01 G01N 21/17-21/61 G01B 11/00-11/30 Practical file (PATOLIS) Patent file (PATOLIS)

Claims (2)

(57) [Claims] 1. A light receiving means for receiving a light from a divided area and outputting a detection signal for each light element for each of a plurality of divided areas obtained by dividing a light receiving spot, and receiving an output of the light receiving means. A variable calculating means for calculating a determination constant based on the detection signal; an area storage means for storing a correspondence relationship between the determination constant and the color; and an output received from the variable calculation means, and the determination is performed by referring to the area storage means. An edge determining means for outputting a color signal specifying a color based on a constant, and a validity determining means receiving an output of each color determining means and outputting a coincidence signal when each color signal matches; processing
A color detection device with a function, wherein the light receiving means has a high light intensity.
Multiple color-enabled filters that detect degrees for red, blue, and green components
Photodiode, which is
Into a bundle of light-receiving fibers with the entrance surface divided into multiple
The output surface at the end of the branch is divided into
Characterized in that it faces the photodiode.
Color detection equipment with ludge processing function. 2. The edge processing function according to claim 1, wherein the variable operation means outputs two or more decision constants each composed of a fraction having the sum of the primary terms of the detection signal as a denominator and one detection signal as a numerator. With color detection equipment.