KR101911425B1 - Autocollimator - Google Patents

Abstract

The present invention relates to an autocollimator including: a laser diode for outputting light; a first collimator lens for converting the light outputted from the laser diode into parallel light; a diaphragm for controlling a size of the light; a beam splitter for allowing the light outputted from the first collimator lens to be irradiated on an angle measurement target object and to be reflected while overlapping with an irradiation path to pass therethrough; a filter installed between the beam splitter and the object to serve as a window for blocking introduction of foreign substances while allowing the light to pass therethrough; a second collimator lens for focusing the light passing through the beam splitter; an image sensor to which the light focused by the second collimator lens is irradiated; a light distribution information processing unit for processing light distribution information of the light irradiated to the image sensor; a wireless communication unit for performing wireless communication with an external terminal; and a microcomputer for calculating angle information of the object based on the information processed by the light distribution information processing unit and a predefined focal distance of the second collimator lens, and controlling the wireless communication unit to provide the angle information to the terminal. According to the present invention, the autocollimator is able to be downsized, a single terminal communicates with a plurality of autocollimators by wireless communication to simultaneously measure angles of various optical components, and coordinate setting is easily performed in a manufacturing process of the autocollimator.

Description

Autocollimator {Autocollimator}

The present invention relates to an autocollimator, and more particularly to an autocollimator which can be miniaturized, can communicate with a plurality of auto-collimators through a single terminal by wireless communication, and can simultaneously measure angles of various optical components, The present invention relates to an auto-collimator capable of easily performing the auto-collimator.

In general, an auto collimator is an angle measuring device that measures the degree of production and alignment of optical components by using a non-contact type light. The light sources used are lamps, LEDs, and laser diodes. And a method of directly observing the light reflected from the object for angle measurement through the eyepiece lens with a human eye or using an image sensor to display the image with a monitor or the like.

Recently, a laser diode is often used as a light source. The laser diode is a point light source and can produce highly precise parallel light. It can increase the light efficiency and reduce power consumption. In addition, since the size of the light source is very small and monochromatic light is used, the optical system can be simplified and the overall size can be reduced.

As a technique relating to a conventional auto collimator, Korean Patent Laid-Open No. 10-1995-0020486 entitled " Multi-purpose auto collimator " has been proposed, which is an autocollimator for measuring an error of an optical axis, A beam splitter, and a beam splitter. The beam splitter transmits and reflects the light projected from the light emitting unit. The light beam is split into a reticle and a lens provided at a focal point position of the objective lens. A reticle section, a camera section for displaying light incident from the reticle section, and an objective lens section for converting light incident through the reticle into parallel light.

Conventional autocollimators and other conventional autocollimators are composed of a light source such as a lamp, an optical unit including a sensor, a process unit for processing sensor information, and a monitor. The beam formed by the sensor is digitally fitted it is possible to increase the precision by fitting and perform various calculations, so that it is possible to measure the angle with high accuracy with small size compared with the optical type which is observed with human eyes.

However, a separate process unit and monitor are required for such digital processing, and a relatively large amount of space is required by requiring a large number of input / output lines and a power supply line. Therefore, the present invention is applicable to a field requiring precise alignment in a narrow space It is difficult to use several auto collimators at the same time.

SUMMARY OF THE INVENTION In order to solve the problems of the prior art as described above, the present invention relates to an automatic collimator using a laser diode as a light source, an auto collimator using an image sensor such as CMOS, It is an object to miniaturize the size of the autocollimator and to make it possible to observe a plurality of auto collimators with a single terminal, thereby improving convenience for the user.

In addition, the present invention includes an information processing unit for performing digital signal processing using an image sensor and performing fitting using the signal to increase the precision of a measurement angle, an LD driver for driving a laser diode, and a wireless communication unit for wireless communication So that it can be miniaturized.

It is also an object of the present invention to easily set reference coordinate system of an auto collimator using a well-known and pre-measured wedge plate.

Other objects of the present invention will become readily apparent from the following description of the embodiments.

According to an aspect of the present invention, there is provided a laser diode comprising: a laser diode for outputting light; A first collimator lens for converting light output from the laser diode into parallel light; A diaphragm for controlling the size of the light; A beam splitter configured to allow light output from the first collimator lens to pass through a path through which light is irradiated on an object for angle measurement and reflected by being superimposed on the path; A filter provided between the beam splitter and the object and serving as a window for blocking the inflow of foreign substances while passing light therethrough; A second collimator lens for condensing light passing through the beam splitter; An image sensor to which light condensed by the second collimator lens is irradiated; A light distribution information processing unit for processing light distribution information of light irradiated to the image sensor; A wireless communication unit for performing wireless communication with an external terminal; And a controller for calculating the angle information of the object on the basis of the information processed by the light distribution information processing unit and the predefined focal distance of the second collimator lens and providing the angle information to the terminal by the wireless communication unit And a microcomputer for controlling the microcomputer.

A first connector connected to a display unit for receiving and displaying the angle information from the microcomputer; A second connector connected to the microcomputer for interlocking with the microcomputer; And an operation signal for adjusting an operation of the laser diode, a laser output adjustment of the laser diode, an entire operation, and a shutter speed of the image sensor, and the microcomputer controls the laser diode and the image sensor And an operation unit for controlling the respective units.

A casing forming an appearance; A tilt stage provided on the bottom surface of the casing to adjust an inclination of the tilt stage; And a post holder fixed to the bottom of the tilt stage, wherein the tilt stage comprises: a movable block provided on a bottom surface of the casing and provided with engaging portions projecting downward from both side portions; A fixing block installed below the movable block so as to be positioned between the engaging portions, and to which the post holder is fixed; A connecting rod having both ends hinged to the fixed block and the movable block so as to be inclined at both sides of the fixed block and the movable block; A horizontal support bolt which is horizontally threadedly coupled to each of the coupling portions and supported by the fixed block, respectively; And a vertical support bolt which is screwed perpendicularly to the fixed block to be supported by the fixed block to adjust the inclination of the movable block from the fixed block.

The microcomputer calculates pixel positions x _p and y _p at a point at which the light amount is maximum in the image sensor and then compares the light amounts within the region of interest to calculate the light amount data extracted along the x and y axes , It is possible to obtain x _p and y _p in pixel units or less.

And further comprising a wedge plate both sides are forming with each other a known inclination angle for reflecting the light of the laser diode, the microprocessor is respectively reflected from a front and rear surfaces of the wedge plate position P _0, P of the light respectively incident to the image sensor ₁ , and when the value obtained by fitting the position of light to the image sensor in accordance with the coordinate system of the image sensor is x, y, x ', y "obtain and said x 'in accordance with, y') and (4 and 5, the coordinated move by the following x", y "a determined, then the angle of the object by the following equation 6 and 7 below, α _x, α _y can be obtained.

&Quot; (3) "

Here, x _o, y _o are the coordinates of P _O.

&Quot; (4) "

&Quot; (5) "

Here, x _o, y _o are coordinates of P _O, x _1, y ₁ are coordinates of P _1.

&Quot; (6) "

Where p is the pitch of the image sensor and f is the focal length of the second collimator lens.

&Quot; (7) "

Where p is the pitch of the image sensor and f is the focal length of the second collimator lens.

According to the auto collimator of the present invention, it is possible to miniaturize the auto collimator, and it is possible to communicate with a plurality of auto-collimators through one terminal by wireless communication and simultaneously measure angles of various optical components, It is possible to enlarge the application field of the optical collimator and to easily set the coordinates in the process of manufacturing the auto collimator.

1 is a configuration diagram showing an autocollimator according to an embodiment of the present invention.
2 is a perspective view illustrating an autocollimator according to an embodiment of the present invention.
3 is a bottom perspective view of an autocollimator according to one embodiment of the present invention.
4 is a side view of an autocollimator according to one embodiment of the present invention.
5 is a perspective view illustrating the interior of an autocollimator according to an embodiment of the present invention.
6 is a plan view showing the interior of an autocollimator according to an embodiment of the present invention.
FIG. 7 is a view for explaining a wedge plate operation of an auto collimator according to an embodiment of the present invention.
8 is a view for explaining the operation of the auto-collimator according to one embodiment of the present invention.
FIG. 9 shows the shape of light that is projected onto an image sensor in an autocollimator according to an embodiment of the present invention.
10 is a view for explaining calculation of a peak point of light quantity by fitting in an autocollimator according to an embodiment of the present invention.
11 is a diagram for explaining a sensor coordinate system and an absolute coordinate system in an autocollimator according to an embodiment of the present invention.
FIG. 12 is an image showing an example of a display (left side) when used as a single unit and a display (right side) displayed when using a plurality of units, respectively, in an autocollimator according to an embodiment of the present invention.

The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated and described in detail in the drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but is to be understood to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention, And the scope of the present invention is not limited to the following examples.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings, wherein like or corresponding elements are denoted by the same reference numerals, and redundant explanations thereof will be omitted.

FIG. 5 is a perspective view showing the inside of an autocollimator according to an embodiment of the present invention, and FIG. 6 is a cross-sectional view of an embodiment of the present invention Fig. 3 is a plan view showing the inside of the auto-collimator according to the first embodiment.

1, 5 and 6, an autocollimator 100 according to an exemplary embodiment of the present invention includes a laser diode 110, a first collimator 120, a diaphragm 130, A beam splitter 140, a filter 210, a second collimator lens 150, an image sensor 160, a light distribution information processing unit 170, a wireless communication unit 180, and a microcomputer 190 .

The auto collimator 100 according to the present invention may be composed of a single terminal 10 and a plurality of auto collimators 100. Alternatively, the auto collimator 100 may include a plurality of terminals 10 have.

The laser diode 110 outputs laser light, which is directly controlled by the microcomputer 190, or may be controlled by the microcomputer 190 through the LD driver 192 as in the present embodiment.

The first collimator lens 120 converts the light output from the laser diode 110 into parallel light and is installed in the casing 220 by the first lens mount 121.

The diaphragm 130 controls the magnitude of light output from the laser diode 110 or converted into parallel light by the first collimator lens 120. For example, as in the present embodiment, A plurality of holes 131 and 132 are formed to be slidably fitted in the diaphragm fixing part 133 formed to be inserted into the casing 220 so that a hole having a desired diameter among the plurality of holes 131 and 132 is inserted into the light- By selectively positioning on the path, the size of the light can be controlled by the diameter of the hole through which the light passes.

The beam splitter 140 allows the light output from the first collimator lens 120 to be irradiated on the object 1 to be angle-measured and reflected by being superimposed on the irradiated path to pass therethrough. For example, the beam splitter 140 May be installed in the casing (220).

The filter 210 may be installed between the beam splitter 140 and the object 1 so as to be disposed on the path of light irradiated to the object 1. The filter 210 may be, Shaped filter mount 211 provided on the front surface of the housing 220 and may serve as a window for blocking the inflow of foreign matter such as dust while passing light.

The second collimator lens 150 condenses the light passing through the beam splitter 140 to converge on the image sensor 160 and can be installed in the casing 220 by the second lens mount 151. That is, the light reflected by the object 1 passes through the filter 210 and the beam splitter 140 and then passes through the second collimator lens 150 having a relatively long focal distance to the image sensor 160 such as CMOS And focuses on it. Conventionally, when the light emitting unit and the light receiving unit share one collimator lens, it is difficult to adjust the light size of the emitted light, and astigmatism is generated by the beam splitter 140, so that the shape of the light is not circular but elongated . Although a square prism can be used to eliminate astigmatism, it is relatively difficult to assemble and is expensive. In the present invention, the collimator lenses 120 and 150 are respectively used in the light-transmitting unit and the light-receiving unit, and the collimator lenses 120 and 150 are bundled using the beam splitter 140. Such a beam splitter 140 does not cause astigmatism because it is in a section where light is parallel light. The light size of the light-transmitting portion can be adjusted by using the diaphragm 130. Therefore, it is possible to make the light size different depending on the size of the object 1.

The image sensor 160 is irradiated with light condensed by the second collimator lens 150. For example, a CMOS or the like may be used, and the image sensor 160 may be installed in the casing 220 by the sensor mount 161. [

The light distribution information processing unit 170 processes the light distribution information of the light irradiated to the image sensor 160 according to a predetermined process and provides the processed light distribution information to the microcomputer 190.

The wireless communication unit 180 performs wireless communication with an external terminal 10. For example, a Wi-Fi module or other communication modules such as 3G and LTE may be used as well as a Bluetooth module . Here, the terminal 10 may be a device that processes information by driving an application or a program, and may perform wireless communication. For example, various information processing and communication devices including a smart phone and a tablet PC may be used have.

The microcomputer 190 calculates the angle information of the object 1 for angle measurement based on the information processed by the light distribution information processing unit 170 and the predefined focal length of the second collimator lens 150 And the calculated angle information can be controlled by the wireless communication unit 180 to be provided to the terminal 10 and can be configured by a CPU or an FPGA and further stored in the memory unit 191 May be provided.

The microcomputer 190 calculates the angle of the object 1 with respect to the focal distance of the light receiving unit such as the focal length f of the second collimator lens 150 and the position of the light in the image sensor 160 (d). < EMI ID = 1.0 > As shown in Fig. 8, when the angle of the object 1 is changed by?, The reflected light becomes 2? By the reflection law. The position d of the beam is the product of tan (2 alpha) and the focal length f of the second collimator lens 150.

Here,? Is the angle of the object.

The auto collimator 100 according to the present invention may be provided with a first connector 231 such as HDMI to be connected to the display unit 20 for receiving and displaying angle information from the microcomputer 190, A second connector 232 such as TCP / IP or RS232 may be provided for interlocking to set up the laser diode 110 and the laser diode 110. In addition, An operation signal for adjusting the operation of the entire auto collimator 100 and the shutter speed of the image sensor 160 is input to the microcomputer 190 so that the laser diode 110 and the image sensor 160 242, 243, and 244 to be controlled. The operation units 241, 242, 243, and 244 include a laser operation switch 241 for turning on / off the operation of the laser diode 110, a laser output for adjusting the laser output of the laser diode 110, An adjustment switch 242, an operation switch 243 for turning on / off the operation of the entire auto-collimator 100, and a shutter speed adjustment switch 244 for adjusting the shutter speed of the image sensor 160. [ And the like.

2 to 4, the autocollimator 100 according to an embodiment of the present invention includes a casing 220 having an outer appearance, a tilt stage 260 configured to adjust the inclination of the bottom surface of the casing 220, And a post holder 270 fixed to the bottom of the tilt stage 260 to the post.

The casing 220 has an internal space for installing and receiving components, and may be provided with a filter 210 serving as a window for outputting light on the front surface. On the rear surface, operation portions 241, 242, 243, 244, Connectors 231 and 232, and a power port 221 for connecting a cable for supplying power.

The tilt stage 260 is provided on the bottom surface of the casing 220 and includes a movable block 261 provided with an engaging portion 261a protruding downward from both side portions and a movable block 261 provided between the movable block 261a and the engaging portion 261a, And a fixed block 262 which is provided below the movable block 261 and to which the post holder 270 is fixed and a fixed block 262 having both ends fixed to both sides of the fixed block 262 and the movable block 261, A connection rod 263 which is hinged to the movable block 261 and a fixing block 262 which are respectively supported by the fixing block 262 by screwing and horizontally passing through the connecting portions 261a horizontally in a row, A horizontal support bolt 264 for fixing the posture of the movable block 261 to the fixed block 262 and a fixed block 262. The horizontal support bolt 264 is screwed perpendicularly to the fixed block 262 and supported by the fixed block 262, The gap is changed in accordance with the inclination of the connecting rod 263 from the block 262 By adjusting the inclination of the lock supporting the movable block 261, which may include a vertical support bolts 265 for adjusting the inclination of the movable block 261.

The post holder 270 is provided with a body 271 formed at one side so as to be formed with a fitting hole so that the post can be inserted and to be tightened and a body 271 which is provided to tighten the incision side of the body 271, And a lever 272 for pressing and securing the post in the frame.

Meanwhile, in the present invention, light emitted from the image sensor 160 is scattered over a plurality of cells, and a method of fitting the light distribution with an appropriate method to obtain an accuracy of less than a pixel is possible. 9, the microcomputer 190 first determines a pixel position x _p , y _p at a point where the light amount is maximum in the image sensor 160, and then finds the pixel position x _p , y _p in the region of interest Compare light quantity. At this time, the output of the laser diode 110 and the shutter speed of the image sensor 160 are adjusted to prevent light from being saturated. Microcomputer 190, as shown in Figure 10 then, extracts the amount of light extracted data along the x-axis and y through the light amount comparison in the area of interest, and (Σ _i (x _i, y _p), Σ _i (x _p , y _i )), and by using an array of the extracted light amount data, x _p and y _p in pixel units or less can be obtained by a Gaussian fitting or the like.

A process of aligning the position of the image sensor 160 with the optical axis and matching the optical axis with the reference coordinate in the process of manufacturing the auto collimator 100 is required. Through this process, the position of the light falling on the image sensor 160 is converted to fit the absolute coordinate axis. For this, as shown in FIG. 7, the wedge plate 280 may further include a wedge plate 280 having opposite sides reflecting the light of the laser diode 110 at mutually known inclination angles. P ₀ and P ₁ are the light reflected by the two faces of the wedge plate 280. The wedge angles formed by both sides are accurately known, P ₀ can be defined as the origin of the absolute coordinate system, and P ₁ can be defined as the X-axis direction. The distance between P ₀ and P ₁ is calculated by the following equation (2).

Here,? Is the wedge angle of the wedge plate 280. Since p is a pitch of the image sensor 160 and is relatively accurate because it is produced by a semiconductor process, the focal distance f of the collimator lens tends to vary depending on errors in the manufacturing process and variations in the wavelength used. The focal length f of the collimator lens, for example, the second collimator lens 150, is obtained.

As shown in FIG. 11, the actual implementation of the optical system for forming two points using the wedge plate 280 is shown. In the image sensor 160, light reflected on the front and rear surfaces of the wedge plate 280 produces two points. The microcomputer 190 acquires the information of the positions P ₀ and P ₁ of the lights respectively reflected from the front and rear surfaces of the wedge plate 280 and incident on the image sensor 160, X ', y' is obtained according to the coordinate movement according to the following expression (3) when the position is a value obtained by fitting the position according to the coordinate system of the image sensor 160, that is, the sensor coordinate system, X ', y''according to the coordinate movement according to the following equations (4) and (5), and the angles α _x and α _y of the object can be obtained by the following equations (6) and (7).

Here, x _o, y _o are the coordinates of P _O.

Here, x _o, y _o are coordinates of P _O, x _1, y ₁ are coordinates of P _1.

Here, p is the pitch of the image sensor 160, and f is the focal length of the second collimator lens 150.

Here, p is the pitch of the image sensor 160, and f is the focal length of the second collimator lens 150.

The auto collimator 100 according to the present invention can measure two or three points at the same time. Two points may be measured like the wedge plate measured above, or diffraction beams such as 0th order, + 1st order, and -1th order emitted from the grating may be measured. When measuring a plurality of points, it is necessary to set the ROI appropriately.

According to the present invention, the terminal 10 such as the autocollimator 100 and the mobile device can be connected via Bluetooth, for example, and a dedicated application is installed in the terminal 10 to communicate with a plurality of auto- can do. The dedicated application can show various angle information received in the auto collimator 100 and can simultaneously display a plurality of auto collimator 100 data (see FIG. 12).

The angular resolution by the auto collimator 100 according to the present invention becomes smaller as the focal length of the second collimator lens 150 is longer and the pitch of the image sensor 160 is shorter. For example, when the focal length of the second collimator lens 150 is 50 mm and the pitch of the image sensor 160 is 4.8 m, the resolution is 15 seconds or less.

According to the auto collimator 100 of the present invention, the terminal 10 such as a smart phone or a tablet PC and the auto collimator 100 can be wirelessly connected to each other wirelessly, for example, by using Bluetooth, So that the data measured by the collimator 100 can be observed and recorded through the display unit of the terminal 10. At this time, the Bluetooth can be connected to a plurality of devices at the same time, so that a plurality of auto collimators 100 can be connected to one terminal 10.

A wireless communication unit 180 such as a board of the image sensor 160, a board of the light distribution information processing unit 170, an LD driver 192 and a Bluetooth module may be mounted in the auto collimator 100, Not only modularization is possible but also all of the operations are carried out by itself, and only the final information is transmitted to the terminal 10 so that the auto-collimator 100 alone can perform all functions.

The terminal 10 and the autocollimator 100 can display, record, and store angle information through an application for providing a corresponding service. At this time, the application can process data transmitted from the plurality of auto collimators 100 .

In addition, since the assembled state of the image sensor 160 does not coincide with the ideal absolute coordinate system, the wedge plate 280 is used as a simple correction method, and correction or conversion is performed .

Although the present invention has been described with reference to the accompanying drawings, it is to be understood that various changes and modifications may be made without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the scope of the appended claims and equivalents thereof.

10: Terminal 20:
30: PC 110: laser diode
120: first collimator lens 121: first lens mount
130: diaphragm 131, 132: hole
133: Aperture fixing unit 140: Beam splitter
141: beam splitter mount 150: second collimator lens
151: second lens mount 160: image sensor
161: Sensor mount 170: Light distribution information processor
180: wireless communication unit 190:
191: Memory section 192: LD driver
210: filter 211: filter mount
220: casing 221: power port
231: first connector 232: second connector
241: Laser operation switch 242: Laser output adjustment switch
243: Operation switch 244: Shutter speed adjustment switch
250: Casing 260: Tilt stage
261: movable block 261a:
262: fixed block 263: connection rod
264: Horizontal support bolt 265: Vertical support bolt
270: post holder 271: body
272: lever 280: wedge plate
290: PCB

Claims (5)

A laser diode for outputting light;
A first collimator lens for converting light output from the laser diode into parallel light;
A diaphragm for controlling the size of the light;
A beam splitter for irradiating an object of angle measurement with light output from the first collimator lens so as to be reflected by being superimposed on the path to be irradiated;
A filter provided between the beam splitter and the object and serving as a window for blocking the inflow of foreign substances while passing light therethrough;
A second collimator lens for condensing light passing through the beam splitter;
An image sensor to which light condensed by the second collimator lens is irradiated;
A light distribution information processing unit for processing light distribution information of light irradiated to the image sensor;
A wireless communication unit for performing wireless communication with an external terminal;
The angle information of the object is calculated on the basis of the information processed by the light distribution information processing unit and the predetermined focal distance of the second collimator lens, and the angle information is provided to the terminal by the wireless communication unit A microcomputer;
A first connector connected to a display unit for receiving and displaying the angle information from the microcomputer;
A second connector connected to the microcomputer for interlocking with the microcomputer;
An operation signal for adjusting an operation of the laser diode, a laser output of the laser diode, an overall operation of the laser diode, and a shutter speed of the image sensor is input to the microcomputer, and the microcomputer controls the laser diode and the image sensor Respectively;
A casing forming an appearance;
A tilt stage provided on the bottom surface of the casing to adjust an inclination of the tilt stage; And
A post holder fixed to a bottom of the tilt stage;
Lt; / RTI >
The tilt stage includes:
A movable block provided on a bottom surface of the casing and provided with engaging portions projecting downward from both side portions;
A fixing block installed below the movable block so as to be positioned between the engaging portions, and to which the post holder is fixed;
A connecting rod having both ends hinged to the fixed block and the movable block so as to be inclined at both sides of the fixed block and the movable block;
A horizontal support bolt which is horizontally threadedly coupled to each of the coupling portions and supported by the fixed block, respectively; And
A vertical support bolt which is screwed perpendicularly to the fixed block to be guided by the fixed block to adjust the inclination of the movable block from the fixed block;
And an auto-collimator. delete delete The method according to claim 1,
The microcomputer,
The pixel position x _p , y _p at the point where the light amount is maximum in the image sensor is searched for, and then the light amount data is compared within the region of interest, and the light amount data extracted along the x- and y- An auto collimator that obtains x _p , y _p in pixel units or less. The method according to claim 1,
Further comprising a wedge plate having opposite sides reflecting the light of the laser diode at mutually known inclination angles,
The microcomputer,
Information on positions P ₀ and P ₁ of light incident on the image sensor, respectively, reflected from the front and rear surfaces of the wedge plate, respectively, and fitting the position of the light to the image sensor according to the coordinate system of the image sensor X ', y' is obtained according to the coordinate movement according to the following expression (3), and x ', y' is calculated according to the coordinate movement according to the following equations (4) , y ", and obtains the angles α _x , α _y of the object by the following equations (6) and (7).
&Quot; (3) "

Here, x _o, y _o are the coordinates of P _O.
&Quot; (4) "

&Quot; (5) "

Here, x _o, y _o are coordinates of P _O, x _1, y ₁ are coordinates of P _1.
&Quot; (6) "

Where p is the pitch of the image sensor and f is the focal length of the second collimator lens.
&Quot; (7) "

Where p is the pitch of the image sensor and f is the focal length of the second collimator lens.

Images