JP5012178B2 - Position dimension measuring device - Google Patents

Description

  The present invention relates to a position dimension measuring apparatus, and more particularly, to a technique capable of easily and reliably performing optical alignment in a position dimension measuring apparatus including a projector and a light receiver.

  Conventionally, a measurement that measures the size or position of a measurement object by irradiating the measurement object with parallel light and measuring the length of the shadow of the measurement object caused by the measurement object blocking the parallel light. The device is known. From the viewpoint of measurement accuracy, in such a measurement apparatus, the direction of the optical axis of the parallel light needs to be adjusted appropriately. For this reason, it is necessary to adjust the relative positions of the projector that emits parallel light and the light receiver that receives the parallel light.

  For example, Japanese Patent Laid-Open No. 4-240506 (Patent Document 1) discloses an optical axis adjustment method for a dimension measuring apparatus using an optical adjuster. The optical adjuster includes a mask unit that blocks a projection beam emitted from the projection unit. Two openings are formed in the mask portion. The mask portion is attached to the light receiving portion so that the two openings coincide with the slits of the light receiving portion, and the positions of both openings are axisymmetric with respect to a line in the slit width direction passing through the center of the slit. Then, while maintaining the state where the output of the light receiving unit when only one opening is closed and the output of the light receiving unit when only the other opening is closed, the output of the light receiving unit is maximized. The position of the light part or the light receiving part is adjusted.

Further, as a method of adjusting the optical axis without using such an optical adjuster, for example, a method in which an output waveform of a light receiver is displayed on an oscilloscope, and a user adjusts the optical axis of parallel light based on the waveform. Is also present.
JP-A-4-240506

  In the case of adjusting the optical axis using the optical axis adjustment method disclosed in Japanese Patent Laid-Open No. 4-240506 (Patent Document 1), an optical adjuster that becomes unnecessary during actual operation is required. In short, when this method is used, since the user cannot easily adjust the optical axis, the number of work steps for adjusting the optical axis increases.

  Further, when the user adjusts the optical axis without using the above-described optical adjuster, there is no means for confirming whether or not the direction of the optical axis has been appropriately adjusted. For this reason, when a user who is not accustomed to adjusting the optical axis adjusts the optical axis, not only does the adjustment take time, but the direction of the optical axis may change little by little every time adjustment is performed. Occurs. When the direction of the optical axis changes, it can be considered that the measurement accuracy is affected by the change in the shadow length and direction of the measurement object.

  In order to prevent such a problem from occurring, for example, a method of connecting the light projecting unit and the light receiving unit using a connecting tool is conceivable. However, when this method is used, since the distance between the light projecting unit and the light receiving unit is fixed, the size of the measurement object is limited. In other words, since the measurement objects that can be measured by the measurement device are limited, the use of the measurement device may be narrowed.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a position shape measuring apparatus capable of easily and reliably adjusting the optical axis. .

  In summary, the present invention is a position dimension measuring apparatus including a light projecting unit, a light receiving element, and a processing unit. The light projecting unit projects a light beam. The light receiving element includes a plurality of light receiving pixels that are arranged in at least a first direction to form a light receiving region, and each of the plurality of light receiving pixels receives a light beam and indicates the amount of light received by each of the plurality of light receiving pixels. Output light reception signal. The processing unit calculates the received light amount distribution of the light beam in the light receiving region by receiving the light reception signal from the light receiving element. The processing unit passes through the center of the light receiving region and the first and second regions that are symmetric about the center line with respect to the center line along the second direction perpendicular to the first direction. Light reception amount balance information relating to the balance between the light reception amount and the light reception amount in the second region is generated and output.

  Preferably, the processing unit generates, as the received light amount balance information, information indicating whether or not the received light amount in the first region and the received light amount in the second region are balanced.

  More preferably, the position dimension measuring device further includes a lighting device that turns on and off by receiving light reception amount balance information from the processing unit. When the received light amount balance information indicates that the received light amount in the first region and the received light amount in the second region are balanced, the lighting device performs one of lighting and extinguishing. When the received light amount balance information indicates that the received light amount in the first region and the received light amount in the second region are not balanced, the lighting device performs the other of turning on and off.

  More preferably, the light receiving element and the processing unit are stored in a common housing. The lighting device is attached to the outer surface of the housing.

  Preferably, the processing unit includes, as the received light amount balance information, information indicating a moving direction of the optical axis required for balancing the received light amount in the first region and the received light amount in the second region. Generate. The direction of movement of the optical axis is the direction from the center of the light receiving region to one end of the light receiving region along the first direction, and the other end of the light receiving region along the first direction from the center of the light receiving region. One of the directions to the part.

  More preferably, the processing unit is based on a first peak value that is a peak value of the received light amount in the first region and a second peak value that is the peak value of the received light amount in the second region. The received light amount balance information is generated.

  More preferably, the processing unit generates received light amount balance information when at least one of the first and second peak values is larger than a predetermined value. When both the first and second peak values are equal to or less than the predetermined value, the processing unit replaces the received light amount balance information with information indicating that the optical axis needs to be moved along the second direction. Generate.

Preferably, the light beam is parallel light.
According to another aspect of the present invention, the position dimension measuring apparatus includes a light projecting unit, a light receiving element, and a processing unit. The light projecting unit projects a light beam including an effective region having an intensity distribution symmetric with respect to the center line in the first direction. The light receiving element includes a plurality of light receiving pixels arranged in at least a first direction to form a light receiving region, and each of the plurality of light receiving pixels receives a light beam in the effective region and receives each of the plurality of light receiving pixels. A light reception signal indicating the amount of light received is output. The processing unit calculates a received light amount distribution of the light beam in the light receiving region by receiving a light receiving signal from the light receiving element. The processing unit calculates, from the received light amount distribution, a position in the first direction corresponding to the center line of the centrally symmetric intensity distribution included in the effective region of the light beam. The processing unit generates information regarding a positional deviation between the calculated position and the center position of the light receiving region.

  Preferably, the light beam has an intensity distribution with a peak intensity at the center of the light beam. The processing unit calculates the position of the intensity peak of the received light amount distribution as the position in the first direction.

  According to the present invention, it is possible to realize a transmission type position / shape measuring apparatus capable of easily and reliably adjusting the optical axis.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following, the same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

  FIG. 1 is a perspective view showing a configuration and an arrangement example of a position dimension measuring apparatus according to the present embodiment. Referring to FIG. 1, a position / dimension measurement apparatus 10 for measuring the position and / or dimension of a measurement target object 300 is arranged on both sides of a region where the measurement target object 300 that has been conveyed is present. The projector 100 and the light receiver 200 are provided.

  The projector 100 is connected to a power source (not shown) via a power cable 105. The light receiver 200 is connected to a controller (not shown) via a cable 205.

  As shown in FIG. 2, the housing 120 of the projector 100 is provided with an opening 110 for projecting emitted light toward the measurement target object 300. A transparent member 170 is provided in the opening 110.

  The parallel light projected from the projector 100 enters the opening 210 provided in the light receiver 200 shown in FIG. The optical axis of the parallel light passes through the center point 111 of the opening 110.

  As will be described in detail later, the opening 210 of the light receiver 200 is provided with an image sensor including a plurality of pixels as a light receiving element. The position dimension measuring apparatus 10 can detect the presence of the measurement target object 300 by detecting a change in the amount of light when the projection light from the projector 100 is blocked by the measurement target object 300. That is, by arranging a plurality of pixels in the opening 210 in a one-dimensional manner, the position and / or dimension of the measurement target object 300 can be measured.

  FIG. 3 is a schematic block diagram showing a configuration of the position dimension measuring apparatus 10 according to the embodiment of the present invention. Referring to FIG. 3, projector 100 includes a semiconductor laser 130, an APC (Auto Power Control) circuit 150, a collimator lens 160, and a transparent member 170 provided in opening 110, which are housed in housing 120. Including. The projector 100 is connected to a power source 400 by a power cable 105 and supplied with operating power.

  The semiconductor laser 130 includes a laser chip 135 and a monitoring photodiode 140. As the semiconductor laser 130, a general configuration in which the laser chip 135 and the photodiode 140 are integrally incorporated can be applied. Laser light output from the laser chip 135 is emitted outside the semiconductor laser 130 through the glass window 137 and also incident on the photodiode 140. That is, the photodiode 140 is arranged to detect the light output of the laser light output from the laser chip 135.

  The APC circuit 150 controls the supply power (typically, supply current) to the laser chip 135 based on the light output detected by the photodiode 140. In general, the power of the laser beam emitted from the laser chip 135 has a characteristic that changes according to the supply current.

  When the light output detected by the photodiode 140 is lower than the light output target value, the APC circuit 150 increases the current supplied to the laser chip 135, and the light output detected by the photodiode 140 becomes the light output target value. If it is higher, the current supplied to the laser chip 135 is decreased. As a result, the APC circuit 150 implements feedback control that maintains the optical output of the laser light output from the laser chip 135 at a constant value that matches the optical output target value. For example, such feedback control makes it possible to keep the laser beam constant with respect to temperature fluctuations.

  The APC circuit 150 further controls lighting of an LED (Light Emitting Diode) 122 indicating that laser light is being emitted and an LED 124 indicating deterioration of the semiconductor laser 130. For example, the APC circuit 150 turns on the LED 122 when the light output detected by the photodiode 140 exceeds a predetermined value. On the other hand, even when a predetermined amount of current is supplied to the laser chip 135, the APC circuit 150 turns on the LED 124 when the light output detected by the photodiode 140 does not reach the reference value for deterioration determination.

  Laser light 500 emitted from the semiconductor laser 130 is converted into a parallel light beam by the collimator lens 160 and emitted from the opening 110. A transparent member 170 is provided in the opening 110 so as to cover the opening 110. Providing the transparent member 170 can prevent dust and the like from entering the projector 100.

  The laser beam 500 emitted from the projector 100 enters the light receiver 200. The light receiver 200 includes an image sensor 250, a processing circuit 260, and an LED 280. The image sensor 250 and the processing circuit 260 are stored in the housing 220, and the LED 280 is attached to the outer surface of the housing 220.

  The image sensor 250 is disposed corresponding to the opening 210 of the housing 220 provided to face the opening 110 on the projector side. The image sensor 250 has a plurality of pixels PX arranged one-dimensionally. Each pixel PX outputs an electrical signal indicating the amount of received light (hereinafter referred to as a pixel signal).

  As the image sensor 250, a CCD image sensor is typically applied. However, a CMOS (Complementary Metal Oxide Semiconductor) image sensor may be used as the image sensor 250 instead of the CCD image sensor. When a CMOS image sensor is used, power consumption can be reduced and pixel signal readout can be speeded up.

  The processing circuit 260 processes a signal indicating the light reception amount of each pixel output from the image sensor 250, thereby creating a light reception amount distribution of a light reception region formed by the plurality of pixels PX.

  In FIG. 3, the optical axis A1 of the laser beam 500 (parallel light beam) output from the projector 100 is shown as a straight line passing through the center point 111 of the opening 110, and the optical axis A2 of the image sensor 250 is the center point of the light receiving region. Shown as a straight line through 271. In order to obtain high measurement accuracy in the position dimension measuring apparatus 10, it is necessary to adjust the relative positions of the projector 100 and the light receiver 200 so that the optical axis A1 and the optical axis A2 coincide.

  When the user adjusts the relative position between the projector 100 and the light receiver 200, that is, when adjusting the optical axis, first, the operation mode of the position dimension measuring apparatus 10 is set to the optical axis adjustment mode by operating the controller 450. . At this time, the processing circuit 260 performs an optical axis adjustment process in response to a command from the controller 450.

  At the time of the optical axis adjustment processing, the processing circuit 260 for the light receiving region formed by the plurality of pixels PX, the received light amount in one of the two regions (first region) symmetric with respect to the center line and the other (first) 2) and the amount of received light.

  The centrally symmetric first and second regions may include a case where two regions separated by a center line are included, but exclude the same region. The reason is that it is only necessary to know the balance between the received light amounts of the first and second regions.

  When the optical axis A1 and the optical axis A2 coincide, the amount of light received in the first region and the amount of light received in the second region are balanced. On the other hand, when the optical axis A1 is deviated from the optical axis A2, the amount of light received in the first region and the amount of light received in the second region are unbalanced.

  The processing circuit 260 generates and outputs received light amount balance information related to the balance between the received light amount in the first region and the received light amount in the second region based on the calculated received light amount distribution in the received light region. Specifically, the processing circuit 260 is in the case where the amount of light received in the first region and the amount of light received in the second region are balanced (the optical axis A1 and the optical axis A2 match). For example, a signal having a logical value “1” is transmitted to the LED 280 to light the LED 280. The processing circuit 260, for example, has a logical value “0” when the amount of light received in the first region and the amount of light received in the second region are not balanced (the optical axis A1 and the optical axis A2 are shifted). Is transmitted to the LED 280 to turn off the LED 280. The logical values “1” and “0” correspond to the “light reception balance information” described above.

  It should be noted that the LED is turned on when the amount of light received in the first region and the amount of light received in the second region are not balanced, and the amount of light received in the first region and the amount of light received in the second region The LED may light up when the balance is achieved. Further, the LED 280 may be turned on according to the logical value “0” when the amount of light received in the first region and the amount of light received in the second region are balanced.

  Based on this light reception balance information, the LED 280 is turned on or off, so that the user can easily confirm the optical axis adjustment result without preparing a device (such as an oscilloscope) for confirming the output of the light receiver 200. . Further, since the LED 280 is attached to the housing 220 in which the image sensor 250 and the processing circuit 260 are housed, the movement of the user's line of sight can be reduced as much as possible when adjusting the optical axis.

  Further, since the processing circuit 260 determines whether or not the optical axis A1 and the optical axis A2 coincide with each other (whether the received light amount is balanced between the first area and the second area), the user can change his / her own The optical axis A1 and the optical axis A2 can be made to coincide with each other more reliably than judging whether the optical axis is adjusted from the output waveform displayed on the oscilloscope based on experience. Therefore, according to the present embodiment, it is possible to realize a transmission type position / shape measuring apparatus capable of easily and reliably adjusting the optical axis.

  Furthermore, according to the present embodiment, since the relative positioning (optical axis adjustment) between the projector 100 and the light receiver 200 is facilitated, the distance between the projector 100 and the light receiver 200 can be increased. Thereby, since the restriction | limiting regarding the magnitude | size of a measuring object becomes loose | gentle, the versatility of a position dimension measuring apparatus can be improved. In addition, since the user can easily adjust the optical axis, it is possible to ensure a predetermined measurement accuracy even if the distance between the projector 100 and the light receiver 200 is increased.

  The processing circuit 260 sends the generated received light amount balance information and the received light amount information of each pixel to the controller 450 connected by the cable 205.

  For example, the controller 450 is configured as shown in FIG. 4, and includes an operation unit 452 for inputting instructions on fine adjustment of the position of the light receiver 200 and measurement condition setting, and a CCD image sensor processed by the processing circuit 260. A display unit 454 showing information corresponding to the output result is displayed. For example, information indicating the edge position of the measurement target object 300 is digitized and displayed on the display unit 454.

  Display unit 454 includes display devices 456 and 458 which are 7-segment display devices. At the time of optical axis adjustment, information on the balance of received light amounts is displayed on the display device 456, and information on the received light amount is displayed on the display device 458.

  Further, inside the controller 450, a processing circuit that processes information from the processing circuit 260 and displays a processing result on the display unit 454, or performs a predetermined process according to an operation result of the operation unit 452 by the user. Is stored.

  Returning to FIG. 3, the light receiver 200 is connected to the power source 410 via the controller 450. Further, by connecting the computer terminal 460 to the controller 450, the measurement result processed by the processing circuit 260 may be displayed on the screen of the computer terminal 460.

  FIG. 5 is a diagram for explaining the optical axis adjustment of the position dimension measuring apparatus 10 according to the present embodiment in more detail. FIG. 6 is a diagram showing the received light amount distribution in the light receiving region of the image sensor 250.

  With reference to FIGS. 5 and 6, in the present embodiment, a first direction in which a plurality of pixels (pixel PX shown in FIG. 3) included in image sensor 250 is arranged is defined as a “left-right direction”.

  The plurality of pixels form a light receiving region 290. The direction from the center point of the light receiving region 290 to one end of the light receiving region 290 along the first direction is leftward, and the other direction of the light receiving region 290 along the second direction from the center point of the light receiving region 290 is The direction to the end is rightward.

The second direction perpendicular to the left-right direction is defined as the “up-down direction”.
FIG. 5 shows a state in which the optical axis of the parallel light beam coincides with the optical axis of the image sensor 250. Since the two optical axes overlap each other, in FIG. 5, the two optical axes in the overlapped state are shown as one optical axis X1. The optical axis X1 passes through the center point 271 of the light receiving region 290, and the optical axis of the image sensor 250 passes through the center point 111 of the opening 110 provided in the projector 100. In this state, the LED 280 on the light receiver 200 side is turned on.

  When adjusting the optical axis, the processing circuit 260 shown in FIG. 3 virtually divides the light receiving area 290 into areas 291 and 292 by a center line passing through the center point 271 and perpendicular to the arrangement direction of the plurality of pixels. Hereinafter, the regions 291 and 292 are also referred to as “left region” and “right region”, respectively. The “right region” and “left region” correspond to the first and second regions described above, respectively.

  In the arrangement state of the projector 100 and the light receiver 200 shown in FIG. 5, the amount of received light is equal in the right region and the left region as shown in FIG. 6 (A). On the other hand, when the projector 100 is shifted in the right direction in FIG. 5, the peak value PR of the received light amount in the right region is larger than the peak value PL of the received light amount in the left region as shown in FIG. Become. When the projector 100 is shifted in the left direction in FIG. 5, the peak value PL is larger than the peak value PR.

  The processing circuit 260 compares each of the peak values PL and PR with the received light amount level threshold value TLVL, and when at least one of the peak values PL and PR is larger than the received light amount level threshold value TLVL, the received light amount described above. Generate quantity balance information. The received light amount level threshold value TLVL can be appropriately determined by design or experiment, for example.

  When the optical axis of the parallel light beam is shifted in the vertical direction, the amount of light of the parallel light beam incident on the light receiving region 290 is small, so that the amount of light received by the light receiving region 290 is reduced (or the amount of received light is almost zero). Become). That is, by moving the optical axis of the parallel light beam in the vertical direction so that at least one of the peak values PL and PR is larger than the received light amount level threshold value TLVL, the optical axis of the parallel light beam is shifted in the vertical direction. Can be eliminated. In such a state, the processing circuit 260 generates the received light amount balance information based on the difference between the peak values PR and PL (= PR−PL). As a result, if the user moves the optical axis of the parallel light beam in the horizontal direction so as to eliminate the deviation of the optical axis of the parallel light beam in the horizontal direction, the optical axis of the parallel light beam is adjusted in any of the vertical, horizontal, and horizontal directions. In other words, it is possible to obtain a state in which the optical axis of the image sensor 250 coincides.

  FIG. 7 is a diagram showing a display of the controller 450 at the time of optical axis adjustment. In this display, the processing circuit inside the controller 450 receives the information of the received light amount peak value and the received light amount from the processing circuit 260 to calculate the received light amount distribution, and generates and outputs the received light amount balance information based on the received light amount distribution. Is realized. The processing circuit inside the controller 450 when performing this display processing implements the “processing unit” of the present invention.

  Referring to FIG. 7, the light receiving balance is displayed by a plurality of vertical bars (bars) on display device 456, and a numerical value indicating the amount of received light is displayed on display device 458. Specifically, each of the plurality of bars is realized by displaying only a part of the 7-segment display.

  FIG. 8 is a diagram illustrating an example of the received light amount balance information displayed on the display device 456 of the controller 450. Referring to FIG. 8, when the projector 100 is shifted in the left-right direction, the processing circuit inside the controller 450 calculates the balance between the received light amount in the right region and the received light amount in the left region as the received light amount balance information. For this purpose, information indicating whether it is necessary to move the optical axis of the parallel light beam leftward or rightward is generated, and the information is output. Display device 456 displays the information using a bar. Specifically, as shown in (A), when it is necessary to move the projector 100 in the left direction, the left end bar is not displayed. When it is necessary to move the projector 100 in the right direction, the right end bar is not displayed.

  If both the peak value PR of the received light amount in the right region and the peak value PL of the received light amount in the left region become lower than the received light amount level threshold value TLVL by shifting the projector 100 in the vertical direction, the inside of the controller 450 The processing circuit generates information indicating that it is necessary to move the optical axis along the vertical direction instead of the received light amount balance information, and outputs the information. Specifically, as shown in (B), the display of the bars at both ends is missing.

  In addition, when there is a light blocking object between the projector 100 and the light receiver 200 or the light projecting surface (or the light receiving surface) is dirty, the number of pixels having a light reception amount smaller than the light reception amount level threshold value TLVL. May exceed a predetermined number. In this case, the processing circuit inside the controller 450 generates and outputs information for causing the display device 456 to perform a display different from both of the above (A) and (B). Specifically, as shown in (C), the central bar is missing from the plurality of bars.

  In this way, the processing circuit inside the controller 450 generates and outputs information indicating whether the optical axis of the parallel light beam is moved in the vertical and horizontal directions. Further, the display device 456 displays this information. Thereby, the user can easily grasp in which direction the optical axis of the parallel light beam should be moved. Therefore, the optical axis can be adjusted easily and reliably.

  FIG. 9 is a flowchart illustrating processing executed by the processing circuit 260 and the controller 450 in FIG. This process is started when the user operates the controller 450 to set the operation mode of the controller 450 to the optical axis adjustment mode.

  With reference to FIGS. 9 and 3, when the processing is started, the processing circuit 260 receives a pixel signal indicating the light reception amount of each pixel from the image sensor 250 and acquires a light reception waveform that is a light reception amount distribution ( Step S1). The processing circuit 260 calculates the peak value of the received light amount in the right region based on this received light amount distribution, and sets the value to the peak value PR (step S2). Similarly, the processing circuit 260 calculates the peak value of the received light amount in the left region based on the received light amount distribution, and sets the value to the peak value PL (step S3). The processing circuit 260 transmits the received light amount of each pixel indicated by the image signal and the peak values PR and PL to the controller 450.

  Subsequently, the processing circuit 260 determines whether the peak value PR is larger than the received light amount level threshold value TLVL or whether the peak value PL is larger than the received light amount level threshold value TLVL (step S4). When peak values PR and PL are both equal to or smaller than received light amount level threshold value TLVL (NO in step S4), processing circuit 260 turns off LED 280 of light receiver 200 (step S7). When at least one of peak values PR and PL is larger than the received light amount level threshold value TLVL (YES in step S4), processing circuit 260 executes the process of step S5.

  In step S5, the processing circuit 260 determines whether or not the absolute value (| PR-PL |) of the difference between the peak value PR and the peak value PL is smaller than the received light amount balance threshold value Tdif. This received light amount balance threshold value Tdif is set to an appropriate value (preferably 0) based on, for example, experiments.

  The processing circuit 260 turns on the LED 280 of the light receiver 200 (step S6) when the absolute value is smaller than the received light amount balance threshold value Tdif (YES in step S5), and turns off the LED 280 otherwise (step S6). Step S7).

  Subsequently, the controller 450 (more specifically, a processing circuit inside the controller 450, but hereinafter simply referred to as “controller”) executes the processes of steps S10 to S13 and SE. The controller 450 determines whether or not the peak value PR is larger than the peak value PL (step S10).

  When the peak value PR is larger than the peak value PL (YES in step S10), the controller 450 reflects the peak value PR on the display of the received light amount by the display device 458 (step S11). In this case, the peak value PR is displayed as the amount of received light. On the other hand, when peak value PL is equal to or higher than peak value PR (NO in step S10), controller 450 reflects peak value PL in the display of received light amount by display device 458 (step S12). In this case, the peak value PL is displayed as the amount of received light.

  When the process of step S11 or S12 ends, the controller 450 calculates the difference between the peak value PR and the peak value PL, and displays the bar display shown in any of (A) to (C) of FIG. 8 based on the difference. Is displayed on the display device 456 (step S13).

  When the absolute value of the difference between the peak value PR and the peak value PL is greater than the received light amount balance threshold value Tdif, the controller 450 determines that the difference between the peak value PR and the peak value PL is a negative value or a positive value. It is determined which one. When the difference between the peak value PR and the peak value PL is a negative value, the controller 450 causes the display device 456 to display the bar so that the leftmost bar is not displayed, and the peak value PR and the peak value are displayed. When the difference from the value PL is a positive value, the display device 456 displays a bar so that the rightmost bar is not displayed. In this way, the controller 450 executes the bar display shown in FIG.

  When the peak values PR and PL are both lower than the received light amount level threshold value TLVL, the controller 450 displays the rest of the plurality of bars excluding the bars at both ends, as shown in FIG. 8B. Let Further, the controller 450 obtains the number of pixels having a light reception amount smaller than the light reception amount level threshold value TLVL based on the image signal. If the number is equal to or greater than the predetermined number, the controller displays the rest of the plurality of bars excluding the central bar, as shown in FIG. 8C.

  When the process of step S13 ends, the controller 450 determines whether or not the user has performed an optical axis adjustment end operation (step SE). When the user performs an optical axis adjustment end operation (YES in step SE), controller 450 ends the optical axis adjustment process. If the user has not performed the optical axis adjustment end operation (NO in step SE), the entire process is returned to step S1.

  Furthermore, according to the present embodiment, the computer terminal 460 receives information on the peak values PR and PL and the received light amount of each pixel from the processing circuit 260 via the controller 450. Based on these pieces of information, the computer terminal 460 performs display for guiding the adjustment direction of the optical axis of the parallel light beam to the user.

  The computer terminal 460 performs the above-described processing by executing information processing using software. In this case, the computer terminal 460 realizes the function of the “processing unit” of the present invention.

  FIG. 10 is a diagram for explaining a first example of display by the computer terminal 460. Referring to FIG. 10, computer terminal 460 displays a waveform representing the received light amount distribution in the light receiving region on the monitor screen based on the received light amount of each pixel. The information on the received light amount distribution displayed on the screen corresponds to the received light amount balance information.

  Note that the light reception waveform displayed on the screen can be stored in the computer terminal 460 or the light reception waveform stored in the computer terminal 460 can be displayed on the screen by a user operation.

  Furthermore, the received light waveform stored in the computer terminal 460 by the user's operation and the current received light waveform can be displayed in an overlapping manner. For example, if the light reception waveform at the past optical axis adjustment is stored in the computer terminal 460, when the user adjusts the optical axis, the current light reception waveform and the light reception waveform stored in the computer terminal 460 substantially coincide with each other. It is possible to adjust the optical axis while moving the projector 100.

  FIG. 11 is a diagram for explaining a second example of display by the computer terminal 460. Referring to FIG. 11, projector 100, light receiver 200, and an arrow for guiding in which direction to move projector 100 up, down, left and right are displayed on the screen of computer terminal 460. Information of this arrow corresponds to received light amount balance information.

  12 is a diagram for explaining the correspondence between the optical axis adjustment direction and the display of the arrows shown in FIG. Referring to FIG. 12, when it is necessary to move projector 100 in the vertical direction, an arrow in the vertical direction is displayed as shown in FIG. Note that the color of the arrow is set to, for example, red so that the user's attention can be drawn.

  When it is necessary to move the projector 100 in the left (or right) direction, as shown in (B), a vertical arrow and a left (or right) arrow are displayed. However, in this case, it is not necessary to move the projector 100 in the vertical direction. For this reason, the up and down arrows are displayed in green so that the user can easily understand that there is no need to move the projector 100 in the up and down direction. On the other hand, the color of the arrow in the left (or right) direction is displayed in red as in (A).

  When the optical axis of the parallel light beam coincides with the optical axis of the image sensor, arrows in the upper, lower, left and right directions are displayed as shown in FIG. Also in this case, the color of the arrow is set to green, for example. As shown in FIGS. 11 and 12, the user can easily adjust the optical axis by guiding the direction in which the projector 100 is moved.

  In this embodiment, the peak value of the received light amount in the right region and the peak value of the received light amount in the left region are used to generate the received light amount balance information. However, the received light amount balance information may be generated using the integrated value of the received light amount in the right region and the integrated value of the received light amount in the left region. However, the calculation load of the processing circuit 260 can be reduced by using the peak value of the amount of received light as in the present embodiment.

  Furthermore, in the present embodiment, the pixel arrangement direction in the image sensor is a one-dimensional direction. However, the optical axis adjustment in the vertical direction may be performed using an image sensor in which pixels are arranged in a two-dimensional direction (matrix) and using the same method as the optical axis adjustment method in the horizontal direction described above.

  Furthermore, in the present invention, it is also possible to generate information relating to the positional deviation between the optical axis of the light beam and the center position of the light receiving region based on the peak position of the light beam. As shown in the present embodiment, the light beam emitted from the light projecting unit includes an effective region having an intensity distribution symmetric with respect to the center line with respect to the pixel arrangement direction (first direction). The light receiving element receives a light beam within the effective area. The processing unit generates a received light amount distribution in the light receiving region based on the light receiving signal from the light receiving element. At this time, the processing unit calculates a position related to the first direction for the center line of the intensity distribution symmetrical to the center line included in the effective region of the light beam from the received light amount distribution. That is, the processing unit calculates a position related to the first direction corresponding to the center line. Then, the processing unit generates information relating to the positional deviation between the calculated position and the center position of the light receiving area.

  Preferably, the light beam has an intensity distribution having a peak at the center thereof. Then, the processing unit calculates the peak position. As a result, the processing unit can generate information regarding the positional deviation between the optical axis of the light beam and the center position of the light receiving region.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a perspective view which shows the structure and the example of arrangement | positioning of the position dimension measuring apparatus according to this Embodiment. It is the figure which looked at the light projector shown in FIG. 1 from the front (light emission side). It is a schematic block diagram which shows the structure of the position dimension measuring apparatus 10 by embodiment of this invention. It is an external view of the controller shown in FIG. It is a figure explaining the optical axis adjustment of the position dimension measuring apparatus 10 which concerns on this Embodiment in detail. FIG. 10 is a diagram showing a received light amount distribution in a light receiving region of the image sensor 250. It is a figure which shows the display of the controller 450 at the time of an optical axis adjustment. It is a figure which shows the example of the light reception amount balance information displayed on the display apparatus 456 of the controller 450. FIG. 4 is a flowchart illustrating processing executed by a processing circuit 260 and a controller 450 in FIG. 3. FIG. 10 is a diagram illustrating a first example of display by a computer terminal 460. FIG. 13 is a diagram for explaining a second example of display by the computer terminal 460. It is a figure explaining the correspondence of an optical axis adjustment direction and the display of the arrow shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Position dimension measuring apparatus, 100 projector, 105 power cable, 110 opening part, 111 center point, 120 housing | casing, 130 semiconductor laser, 135 laser chip, 137 glass window, 140 photodiode, 150 APC circuit, 160 collimating lens, 170 Transparent member, 200 light receiver, 205 cable, 210 opening, 220 housing, 250 image sensor, 260 processing circuit, 271 center point, 290 light receiving area, 291, 292 area, 300 measurement object, 400, 410 power supply, 450 Controller, 452 operation unit, 454 display unit, 456, 458 display device, 460 computer terminal, 500 laser beam, A1, A2, X1 optical axis, PX pixel.

Claims (7)

A light projecting unit that projects a light beam;
A plurality of light receiving pixels arranged in at least a first direction to form a light receiving region, and each of the plurality of light receiving pixels receives the light beam and indicates the amount of light received by each of the plurality of light receiving pixels. A light receiving element for outputting a signal;
A processing unit that calculates a received light amount distribution of the light beam in the light receiving region by receiving the light reception signal from the light receiving element;
The processing unit passes through the center of the light receiving region, and the first and second regions are symmetric about a center line along a second direction perpendicular to the first direction . The first peak value, which is the peak value of the received light amount of each of the plurality of light receiving elements in the region, and the peak value of the received light amount of each of the plurality of light receiving elements in the second region. Based on the peak value of 2, the light reception amount balance information relating to the balance between the light reception amount in the first region and the light reception amount in the second region is generated and output ,
The processing unit generates a light receiving amount distribution in the light receiving region from a light receiving signal output from each of a plurality of light receiving pixels, and calculates the first and second peak values based on the light receiving amount distribution. Position dimension measuring device.   The processing unit generates information indicating whether or not the received light amount in the first region and the received light amount in the second region are balanced as the received light amount balance information. The position dimension measuring device described in 1. The position dimension measuring device includes:
A lighting device for turning on and off by receiving the received light amount balance information from the processing unit;
When the received light amount balance information indicates that the received light amount in the first region and the received light amount in the second region are balanced, the lighting device is turned on or off. If the received light amount balance information indicates that the received light amount in the first region and the received light amount in the second region are not balanced, the other of turning on and off is performed. The position dimension measuring apparatus according to claim 2. The light receiving element and the processing unit are stored in a common housing,
The position measurement device according to claim 3, wherein the lighting device is attached to an outer surface of the housing. The processing unit indicates, as the received light amount balance information, a direction of movement of the optical axis required for balancing the received light amount in the first region and the received light amount in the second region. Generate information,
The direction of movement of the optical axis is the direction from the center of the light receiving area to the one end of the light receiving area along the first direction, and the direction from the center of the light receiving area to the first direction. The position dimension measuring apparatus according to claim 1, wherein the position dimension measuring apparatus is in one of directions extending to the other end of the light receiving region. The processing unit generates the received light amount balance information when at least one of the first and second peak values is larger than a predetermined value, and both the first and second peak values are the predetermined value. the following cases, instead of the amount of light received balance information, the generating the information indicating that the optical axis must be moved along the second direction, the position dimension measuring apparatus according to claim 1 .   The position dimension measuring apparatus according to claim 1, wherein the light beam is parallel light.

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