KR20180097347A - Optical position sensing device - Google Patents

Abstract

Disclosed is an optical position detection apparatus. According to an embodiment of the present invention, the optical position detection apparatus comprises: a first optical fiber receiving a laser pulse; a photodetector detecting a laser pulse, received by the first optical fiber, to output the laser pulse as an electrical signal; and a controller calculating the position of the laser pulse based on the electrical signal.

Description

[0001] OPTICAL POSITION SENSING DEVICE [0002]

The following embodiments relate to an optical position sensing device.

The optical position sensing device is a device that indicates the position where the laser light is fitted when the laser light is hit by the detection part and controls the position of the light transmitting part or the light receiving part so that the position of the light is fixed at a predetermined position Can be used.

The optical position sensing device can be applied to a technique in which a laser beam is irradiated on a moving object to track an object moving.

For example, laser beam tracking technology can be applied to satellite laser ranging (SLR) systems that track the orbit of a satellite by attaching a laser reflector to the satellite, a laser tracker ), Laser weapon tracking systems, and so on.

In addition, the optical position sensing device can be applied to atmospheric optical communication technology and frequency standard transmission technology which transmit and receive laser light to a long distance to the atmosphere, and can maintain an optical link between a light emitting portion and a light receiving portion in an atmospheric disturbance and vibration environment.

The optical position sensing technology uses a photo detector consisting of a 2D surface to detect more current in the electrode near the laser light detection area and a method in which a current is detected in each photodetector using a quadrant photodetector A method of detecting the position by comparing the magnitudes of the signals or a method of detecting the position by acquiring an image of the laser light using a camera (for example, a CCD camera or a CMOS camera).

However, existing optical position sensing technologies can not simultaneously transmit and receive laser light. In order to simultaneously transmit and receive laser light, a beam splitter (BS) and a beam splitter An optical part such as a lens is additionally required. Optical parts, such as additional light splitters and lenses, can increase the complexity of the system, cause light loss, and cause problems with optical alignment.

Embodiments can provide a technique for calculating the position of a received laser pulse.

Embodiments can also provide a technique for controlling an actuator or a scanning mirror based on the position of a calculated laser pulse.

The optical position sensing apparatus includes a first optical fiber for receiving a laser pulse, a photo detector for sensing a laser pulse received by the first optical fiber and outputting the electrical pulse as an electrical signal, And a controller for calculating a position of the laser pulse based on the electrical signal.

The apparatus may further comprise a second optical fiber that emits a laser pulse and receives a laser pulse reflected from the reflector.

The apparatus may further include an optical fiber bundle including the first optical fiber and the second optical fiber.

The photodetector may be connected to the first optical fiber.

The apparatus may further include a lens that collimates the laser pulse or focuses the laser pulse.

The first optical fiber may include at least one optical fiber.

The second optical fiber may be positioned between the at least one optical fiber.

The first optical fiber may include four optical fibers, and the photodetector may include a first photodetector, a second photodetector, a third photodetector, and a fourth photodetector, each of which is connected to the four optical fibers. have.

The four optical fibers may be symmetrically arranged vertically and horizontally.

The controller can calculate the position of the laser pulse based on the equation.

The optical fiber bundle may be implemented as a fan-out optical fiber bundle, a double clad fiber coupler, a multi-core fiber (MCF), or a multichannel wave guide .

The apparatus may further include a scanning mirror for controlling a traveling direction by reflecting the laser pulse, and the controller may control the direction of the scanning mirror based on the position.

The apparatus may further include an actuator for controlling a position of the first optical fiber and the second optical fiber, and the controller may control a direction of the driving body based on the position.

1A shows an example of a block diagram of an optical position sensing system according to an embodiment.
1B shows another example of a block diagram of an optical position sensing system according to an embodiment.
Fig. 2 shows a block diagram of the optical position sensing apparatus shown in Fig. 1A.
FIG. 3 is a view for explaining the optical fiber shown in FIG. 2,
4A is a structural view of an optical position sensing apparatus according to an embodiment.
4B is a cross-sectional view of the optical position sensing device shown in FIG. 4A.
5A is an example of a diagram for explaining an operation in which the controller controls the scanning mirror.
5B is another example of a diagram for explaining the operation of the controller for controlling the scanning mirror.
6A is an example of a diagram for explaining an operation of the controller for controlling the driver.
6B is another example of a diagram for explaining an operation of the controller for controlling the driver.

It is to be understood that the specific structural or functional descriptions of embodiments of the present invention disclosed herein are presented for the purpose of describing embodiments only in accordance with the concepts of the present invention, May be embodied in various forms and are not limited to the embodiments described herein.

Embodiments in accordance with the concepts of the present invention are capable of various modifications and may take various forms, so that the embodiments are illustrated in the drawings and described in detail herein. However, it is not intended to limit the embodiments according to the concepts of the present invention to the specific disclosure forms, but includes changes, equivalents, or alternatives falling within the spirit and scope of the present invention.

The terms first, second, or the like may be used to describe various elements, but the elements should not be limited by the terms. The terms may be named for the purpose of distinguishing one element from another, for example without departing from the scope of the right according to the concept of the present invention, the first element being referred to as the second element, Similarly, the second component may also be referred to as the first component.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between. Expressions that describe the relationship between components, for example, "between" and "immediately" or "directly adjacent to" should be interpreted as well.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, the terms " comprises ", or " having ", and the like, are used to specify one or more of the features, numbers, steps, operations, elements, But do not preclude the presence or addition of steps, operations, elements, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the meaning of the context in the relevant art and, unless explicitly defined herein, are to be interpreted as ideal or overly formal Do not.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, the scope of the patent application is not limited or limited by these embodiments. Like reference symbols in the drawings denote like elements.

FIG. 1A shows an example of a block diagram of an optical position sensing system according to an embodiment, and FIG. 1B shows another example of a block diagram of an optical position sensing system according to an embodiment.

Referring to FIG. 1A, an optical position sensing system 10 includes an optical position sensing device 100 and a base station 200.

The optical position sensing device 100 may be optically connected to the base station 200. That is, the optical position sensing apparatus 100 may form an optical link with the base station 200. For example, the optical position sensing device 100 may perform laser optical communication with the base station 200.

The laser optical communication may be uni-directional communication or one-way communication, two-way communication, or omni-directional communication.

That is, in the case of unidirectional communication, the optical position sensing apparatus 100 can receive (or receive) laser pulses from the base station 200. At this time, the base station 200 may be an external transmitting apparatus.

In the case of bidirectional communication or omnidirectional communication, the optical position sensing apparatus 100 may transmit (or transmit) laser pulses to the base station 200 and receive (or receive) laser pulses from the base station 200.

Referring to FIG. 1B, the optical position sensing system 20 includes an optical position sensing device 100 and a reflector 300.

The optical position sensing apparatus 100 can transmit (or transmit) laser pulses to and from the reflector 300 and receive (or receive) laser pulses reflected from the reflector 300. The reflector 300 may be an object to be subjected to distance measurement. In other words, the optical position sensing apparatus 100 may measure the distance to the reflector 300 based on the laser pulse reflected from the reflector 300.

The optical position sensing apparatus 100 shown in Figs. 1A and 1B can calculate the position of the received laser pulse based on the laser pulse. For example, the optical position sensing device 100 determines whether the laser pulse is located at the center, right, left, top, bottom, right, bottom, Whether it is located in the upper left corner, the lower left corner, and so on.

The optical position sensing apparatus 100 may calculate the coordinates of the received laser pulses. The coordinates of the laser pulse may be two-dimensional coordinates or three-dimensional coordinates. If the coordinates of the laser pulse are two-dimensional coordinates, they may include x-axis coordinates and y-axis coordinates. If the coordinates of the laser pulse are three-dimensional coordinates, it may include an x-axis coordinate, a y-axis coordinate, and a z-axis coordinate.

The optical position sensing apparatus 100 can maintain the light amount of the laser pulse transmitted and received to be constant when there is disturbance. Disturbance can include vibration, shaking, atmospheric disturbance, refraction, reflection, scattered reflection, or diffraction.

The optical position sensing apparatus 100 can control the direction of the laser pulse transmitted or received or control the position of the laser pulse to keep the light amount of the laser pulse transmitting and receiving on the basis of the calculated coordinates. That is, the optical position sensing apparatus 100 can operate as a laser tracker (LT).

As an example, the optical position sensing device 100 may include a scanning mirror. The optical position sensing apparatus 100 can control the scanning mirror based on the calculated coordinates and control the direction of the laser pulse. That is, the scanning mirror can change the direction of the laser pulse transmitted and received by the optical position sensing apparatus 100. The amount of light of the laser pulse transmitted and received can be kept constant.

As another example, the optical position sensing device 100 may include an actuator. The optical position sensing apparatus 100 can control the driver based on the calculated coordinates and control the position of the optical position sensing apparatus 100. [ The driving body may be attached to the optical position sensing device 100. That is, the driver changes the position in response to the control of the optical position sensing device 100, and thus the position of the optical position sensing device 100 may change. The amount of light of the laser pulse transmitted and received can be kept constant.

Fig. 2 shows a block diagram of the optical position sensing apparatus shown in Fig. 1A.

Referring to FIG. 2, the optical position sensing apparatus 100 includes an optical fiber 110, a photo detector 120, and a controller 130.

The optical fiber 110 can receive (or receive) laser pulses. The optical fiber 110 may include at least one optical fiber. That is, the optical fiber 110 may be implemented with a plurality of optical fibers.

The optical fiber 110 may transmit the received laser pulse to the photodetector 120. The photodetector 120 may be implemented with a plurality of photodetectors and may be connected to each optical fiber 110.

The photodetector 120 may generate an electrical signal based on the received laser pulse and output the electrical signal to the controller 130. The electrical signal may be a current signal or a voltage signal. For example, when the light amount of the laser pulse received by the photodetector 120 is high, the photodetector 120 may generate an electrical signal having a high current or voltage. When the light amount of the laser pulse received by the photodetector 120 is low, the photodetector 120 can generate an electric signal having a low current or voltage.

The magnitudes of the laser pulses received by the respective optical fibers 110 may be different. That is, the magnitude of the electrical signal generated by each photodetector 120 may be different.

The controller 130 may calculate the position of the laser pulse based on the different electrical signals. The position of the laser pulse can be expressed in coordinates.

The controller 130 can control the direction of the laser pulse transmitted or received or control the position of the optical position sensing device 100 based on the calculated coordinates to maintain a constant amount of the laser pulse transmitted and received.

FIG. 3 is a view for explaining the optical fiber shown in FIG. 2, FIG. 4A is a structural view of the optical position sensing device according to an embodiment, and FIG. 4B is a sectional view of the optical position sensing device shown in FIG. 4A.

Referring to FIGS. 3 to 4B, the optical fiber 110 includes a first optical fiber 111 and a second optical fiber 112. The first optical fiber 111 and the second optical fiber 112 may be implemented as an optical fiber bundle 140. That is, the optical fiber bundle 140 may include an optical fiber 110.

The optical fiber bundle 140 may be implemented as a fan-out optical fiber bundle, a double clad fiber coupler, a multi-core fiber (MCF), or a multichannel wave guide have. The optical position sensing apparatus 100 can improve the system complexity by using the optical fiber bundle 140. [

The first optical fiber 111 can receive (or receive) laser pulses. The received laser pulse may be focused (or focused) through a lens. That is, the optical position sensing apparatus 100 may further include a lens.

The first optical fiber 111 may be implemented as a plurality of optical fibers 111-1 through 111-4. The plurality of optical fibers 111-1 to 111-4 may be symmetrically arranged in the up, down, left, and right directions. Each first optical fiber 111 may be connected to each photodetector 120. That is, the first optical fiber 111-1 is connected to the first optical detector 120-1, the first optical fiber 111-2 is connected to the second optical detector 120-2, and the first optical fiber 111-3 may be connected to the third photodetector 120-3 and the first optical fiber 111-4 may be connected to the fourth photodetector 120-4. The first optical fiber 111 may be referred to as a position sensing fiber.

The second optical fiber 112 can transmit and receive a laser pulse. That is, the second optical fiber 112 may serve as a path of a laser pulse to be transmitted to the base station 200 or the reflector 300, and a laser pulse to be received from the base station 200 or the reflector 300. When the second optical fiber 112 emits a laser pulse, the lens may collimate the laser pulse. When the second optical fiber 112 receives a laser pulse, the lens can focus (or focus) the laser pulse. The second optical fiber 112 may be called a signal fiber.

The second optical fiber 112 may be located between the first optical fibers 111-1 through 111-4. That is, the first optical fibers 111-1 to 111-4 may be implemented symmetrically with respect to the second optical fiber 112. [

For example, the first optical fiber 111-1 and the first optical fiber 111-2 are y-axis symmetric, the first optical fiber 111-1 and the first optical fiber 111-3 are zero-point symmetric, 1 optical fiber 111-1 and the first optical fiber 111-4 may be x-axis symmetric.

The first optical fiber 111-2 and the first optical fiber 111-3 may be symmetrical with respect to the x axis and the first optical fiber 111-2 and the first optical fiber 111-4 may be symmetrical with respect to the zero point.

The first optical fiber 111-3 and the first optical fiber 111-4 may be y-axis symmetric.

The sizes of the laser pulses received by the first optical fibers 111-1 to 111-4 may be different. That is, the sizes of electrical signals generated by the respective photodetectors 120-1 to 120-4 may be different. For example, the first photodetector 120-1 generates an electrical signal of PD 1, the second photodetector 120-2 generates an electrical signal of PD 2, and the third photodetector 120-3 May generate an electrical signal of PD 3 and a fourth photodetector 120-4 may generate an electrical signal of PD 4.

Each of the photodetectors 120-1 to 120-4 can transmit the generated electrical signal to the controller 130.

The controller 130 can calculate the position of the laser pulse based on Equation (1).

Here, x is the x- axis coordinate of the received laser pulse, y is the y- axis coordinate of the received laser pulse, PD 1 is the electrical signal output by the first photodetector 120-1, PD 2 is the second PD 3 is an electrical signal output by the third photodetector 120-3 and PD 4 is an electrical signal output by the fourth photodetector 120-4 .

Based on the calculated coordinates, the controller 130 can control the direction of the laser pulses to be transmitted or received, or can control the position of the laser pulses to maintain the light amount of the laser pulses transmitted and received at a constant level. The operation of controlling the direction of the laser pulse transmitted or received by the controller 130 or controlling the position of the optical position sensing apparatus 100 will be described later with reference to Figs. 5A to 6B.

In FIGS. 4A and 4B, the first optical fiber 111 is illustrated as being implemented in four for the sake of convenience. However, the present invention is not limited to this, and the first optical fibers 111 may be implemented in a plurality.

FIG. 5A is an example of a diagram for explaining an operation of the controller for controlling a scanning mirror, and FIG. 5B is another example of a diagram for explaining an operation of the controller for controlling the scanning mirror.

Referring to FIGS. 5A and 5B, the controller 130 may control the scanning mirror 150. FIG. For example, the controller 130 controls the scanning mirror 150 so that the light amount of the received laser pulse is maximized or constant.

The optical position sensing device 100 can transmit laser pulses to the reflector 300. [ At this time, the lens 170 can collimate the laser pulse. That is, the laser pulse may be parallel rays.

The scanning mirror 150 can change the direction of the laser pulse. For example, the scanning mirror 150 may reflect the laser pulse and transmit it to the reflector 300.

The reflector 300 may reflect the laser pulse and transmit it to the scanning mirror 150.

The scanning mirror 150 may change the direction of the laser pulse reflected from the reflector 300 and transmit it to the lens 170.

At this time, the lens 170 can condense (or concentrate) the received laser pulse and output it to the optical fiber bundle 140. A first optical fiber (111-1 ~ 111-4) and the light detector to be connected (120-1 ~ 120-4) may output to the controller 130 to generate a respective electric signal (PD-1, PD 4).

The controller 130 can calculate the position of the received laser pulse based on the electrical signals PD1 to PD4 . The controller 130 can control the scanning mirror 150 based on the calculated position of the laser pulse.

For example, the controller 130 can control the scanning mirror 150 up, down, left, or right. When the laser pulse is located at the lower end, the controller 130 controls the scanning mirror 150 up and down so that the laser pulse is positioned at the center. When the laser pulse is located on the right side, the controller 130 controls the scanning mirror 150 to be horizontally positioned to center the laser pulse. In addition, when the laser pulse is located at the right upper end, the controller 130 controls the scanning mirror 150 to be vertically or horizontally positioned so that the laser pulse is located at the center.

Fig. 6A is an example of a diagram for explaining an operation of the controller for controlling the driver, and Fig. 6B is another example of a diagram for explaining an operation of the controller for controlling the driver.

Referring to FIGS. 6A and 6B, the controller 130 may control the driving body 160. For example, the controller 130 may control the driving body 160 so that the light amount of the received laser pulse is maximized or constant.

The optical position sensing device 100 can transmit laser pulses to the reflector 300. [ At this time, the lens 170 can collimate the laser pulse. That is, the laser pulse may be a parallel ray.

The reflector 300 may reflect the laser pulse and transmit it to the lens 170.

The lens 170 can condense (or concentrate) the received laser pulse and output it to the optical fiber bundle 140. A first optical fiber (111-1 ~ 111-4) and the light detector to be connected (120-1 ~ 120-4) may output to the controller 130 to generate a respective electric signal (PD-1, PD 4).

The controller 130 can calculate the position of the received laser pulse based on the electrical signals PD1 to PD4 . The controller 130 can control the driving body 160 based on the calculated position of the laser pulse. The driving body 160 may be attached to the optical position sensing device 100.

For example, the controller 130 can control the driver 160 up, down, left, or right. When the laser pulse is located at the lower end, the controller 130 controls the driving body 160 up and down so that the laser pulse is positioned at the center. When the laser pulse is located on the right side, the controller 130 controls the driving body 160 to the left and right so that the laser pulse is located at the center. In addition, when the laser pulse is located at the right upper end, the controller 130 controls the driving body 160 to be vertically or horizontally positioned so that the laser pulse is located at the center.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the apparatus and components described in the embodiments may be implemented within a computer system, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA) , A programmable logic unit (PLU), a microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to execution of the software. For ease of understanding, the processing apparatus may be described as being used singly, but those skilled in the art will recognize that the processing apparatus may have a plurality of processing elements and / As shown in FIG. For example, the processing unit may comprise a plurality of processors or one processor and one controller. Other processing configurations are also possible, such as a parallel processor.

The software may include a computer program, code, instructions, or a combination of one or more of the foregoing, and may be configured to configure the processing device to operate as desired or to process it collectively or collectively Device can be commanded. The software and / or data may be in the form of any type of machine, component, physical device, virtual equipment, computer storage media, or device , Or may be permanently or temporarily embodied in a transmitted signal wave. The software may be distributed over a networked computer system and stored or executed in a distributed manner. The software and data may be stored on one or more computer readable recording media.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (13)

A first optical fiber for receiving a laser pulse;
A photo detector for detecting a laser pulse received by the first optical fiber and outputting the laser pulse as an electrical signal; And
A controller for calculating a position of the laser pulse based on the electrical signal,
The optical position detection device comprising:
The method according to claim 1,
A second optical fiber which emits a laser pulse and receives a laser pulse reflected from the reflector,
Further comprising an optical position sensor.
3. The method of claim 2,
An optical fiber bundle including the first optical fiber and the second optical fiber,
Further comprising an optical position sensor.
The method according to claim 1,
The photodetector includes:
And a second optical fiber
Optical position sensing device.
The method according to claim 1,
A lens that collimates the laser pulse or focuses the laser pulse,
Further comprising an optical position sensor.
The method according to claim 1,
Wherein the first optical fiber comprises:
Comprising at least one optical fiber
Optical position sensing device.
3. The method of claim 2,
Wherein the second optical fiber comprises:
And at least one optical fiber
Optical position sensing device.
The method according to claim 6,
Wherein the first optical fiber comprises:
Four optical fibers
Lt; / RTI >
The photodetector includes:
A first photodetector, a second photodetector, a third photodetector, and a fourth photodetector, which are respectively connected to the four optical fibers,
The optical position detection device comprising:
9. The method of claim 8,
The four optical fibers may include,
It is implemented symmetrically
Optical position sensing device.
10. The method of claim 9,
The controller comprising:
The position of the laser pulse is calculated based on the following equation
Optical position sensing device.
[Mathematical Expression]

Here, PD 1 is the electrical signal of the first photodetector outputs, PD 2 is the electrical signal to the second optical detector output, PD 3 is an electric signal to the third optical detector output, PD 4 is X is the x- axis coordinate of the received laser pulse, and y is the y- axis coordinate of the received laser pulse.
11. The method of claim 10,
The optical fiber bundle,
It is implemented as a fan out fiber bundle, a double clad fiber coupler, a multi-core fiber (MCF), or a multichannel waveguide.
Optical position sensing device.
The method according to claim 1,
A scanning mirror for controlling the traveling direction by reflecting the laser pulse,
Further comprising:
The controller comprising:
And controls the direction of the scanning mirror based on the position.
3. The method of claim 2,
An actuator for controlling the positions of the first optical fiber and the second optical fiber,
Further comprising:
The controller comprising:
And controls the direction of the driving body based on the position.

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