Light receiver detection method, light receiving sensor and laser line projector

Abstract

The application discloses a light receiver detection method, a light receiving sensor and a laser line projector, and belongs to the technical field of laser line projectors. The detection method comprises the following steps: (1) calibrating the height range of the photodiode; and (2) detecting and calculating the position of the laser light. The laser is projected to the light receiver, the electric signal amplitude of each photodiode is recorded, the maximum electric signal amplitude is determined, and the relative position of the laser light on the light receiver is determined according to the calibration value range in step (1) after the position of the laser light is calculated. According to the light receiver detection method provided by the application, the position of the laser light can be accurately judged, and the coordinates of the position can be accurately determined to 1 mm. In the application, there is no gap between the light receiving areas of the photodiodes in the light receiver. No matter where the laser light is irradiated, the specific position of the signal can be recognized and judged by the light receiver.

Description

Technical Field

[0001] This invention relates to the field of laser line projector technology, and in particular to a method for detecting a light receiver, a light receiving sensor, and a laser line projector. Background Technology

[0002] As a core tool in modern engineering surveying, the laser line projector achieves spatial calibration for scenarios such as building positioning, equipment installation, and interior decoration by projecting high-precision laser reference lines. In this system, the optical receiver, as the key terminal for detecting laser signals, directly affects the final construction quality.

[0003] Current optical receivers generally employ regularly arranged photodiode (PD) arrays to capture laser signals. Traditional PD designs rely on discretely distributed photosensitive units, determining the laser emission position by comparing the output current intensity of each unit. However, in this case, the receiver can only accurately output the center coordinates when the laser hits the center of the PD board. In practical applications, the light spot often deviates from the center due to instrument jitter, projection angle deviation, or long-distance divergence, falling into the boundary area of ​​the PD units. In this case, due to the physical gaps between PD units and the lack of continuous position sensing capability, the optical receiver can only determine the direction of the light beam, such as above or below the center, based on the single PD unit with the strongest signal, and cannot calculate the precise coordinates of the light spot. This leads to reduced positioning accuracy for non-center points, especially in scenarios requiring millimeter-level precision such as wall flatness detection and floor leveling. The PD boards in existing optical receivers are insufficient to meet the requirements for continuous position feedback. Summary of the Invention

[0004] To address the problem of low detection accuracy of optical receivers in existing laser line projectors, this invention aims to provide an optical receiver detection method, an optical receiver sensor, and a laser line projector.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] Firstly, this invention provides a method for detecting a light receiver, wherein the light receiver includes at least two columns of photodiodes, and the photodiodes in adjacent columns are staggered. Detection is performed according to the following steps:

[0007] (1) Calibrate the height range of the photodiode;

[0008] Fix the light receiver on a standard height ruler, use a standard light source to align with the center position of the nth photodiode, and calculate the ratio of the electrical signal amplitude at the center positions of the (n+1)th and (n-1)th photodiodes respectively;

[0009] Starting from the center position of the nth photodiode, move the standard height ruler up and down respectively, and record the ratio of the electrical signal amplitude at the center positions of the (n+1)th and (n-1)th photodiodes in sequence to form a calibration range;

[0010] (2) Detect and calculate the position of the laser beam;

[0011] The laser beam is projected onto the optical receiver, the electrical signal amplitude of each photodiode is recorded, the maximum electrical signal amplitude is determined, and the position of the laser beam is calculated and then the relative position of the laser beam on the optical receiver is determined according to the calibration range in step (1).

[0012] In one embodiment, the light-receiving area of ​​the photodiode is collinear with the light-receiving areas of two adjacent photodiodes in an adjacent column.

[0013] In one embodiment, the method for determining the ratio of the electrical signal amplitude at the center position of the (n+1)th and (n-1)th photodiodes in step (1) is as follows:

[0014]

[0015] V a V is the electrical signal amplitude at the center position of the (n-1)th photodiode. c The amplitude of the electrical signal at the center position of the (n+1)th photodiode is given.

[0016] In one embodiment, in step (1), the standard height gauge moves 1 mm each time, moving m times upwards and m times downwards, where m is no more than... The largest integer is L, where L is the light-receiving length of the photodiode.

[0017] In one embodiment, the method for calculating the position of the laser beam in step (2) is as follows:

[0018]

[0019] f is the number of the photodiode corresponding to the maximum amplitude of the electrical signal, and L is the light-receiving length of the photodiode.

[0020] 6. The optical receiver detection method according to claim 5, characterized in that the method for calculating the relative position of the laser beam on the optical receiver in step (2) is as follows:

[0021]

[0022] H = D - (f - 1) × K,

[0023] Xf V is the ratio of the electrical signal amplitude at the center position of the f-th photodiode. f+1 V is the electrical signal amplitude at the center position of the (f+1)th photodiode. f-1 The amplitude of the electrical signal at the center position of the (f-1)th photodiode;

[0024] when At that time, the laser beam is located at the center of the f-th photodiode;

[0025] when At that time, the laser beam is positioned above the f-th photodiode, and then X... f Compare with the calibration value range specified in step (2);

[0026] when At that time, the laser beam is located below the f-th photodiode, and then X... f Compare with the calibration value range specified in step (2).

[0027] Secondly, the present invention also provides a light receiving sensor including a light receiver, the light receiver including at least two columns of photodiodes, the photodiodes in adjacent columns being staggered from each other, the light receiver detecting the position of the laser beam according to the detection method described in any of the above claims.

[0028] Finally, the present invention also provides a laser line projector, which is used in conjunction with the aforementioned light receiving sensor.

[0029] In the optical receiver described in this invention, there are no gaps between the light-receiving areas of the photodiodes. Regardless of the location of the laser beam, the optical receiver can identify and determine the specific location of the signal. Furthermore, because each photodiode is an independent unit, the blind zone is extremely small, resulting in more accurate location determination and eliminating missed detections. The optical receiver detection method provided by this invention can accurately determine the position of the laser beam, with coordinates accurate to 1 mm.

[0030] To make the above-mentioned features and advantages of the invention more apparent and understandable, specific embodiments are described below, and detailed descriptions are provided in conjunction with the accompanying drawings. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the arrangement of photodiodes in the optical receiver of the present invention.

[0032] Figure 2 This is a schematic diagram of the structure of the optical receiver in the detection method provided by the present invention. Detailed Implementation

[0033] To make the objectives and technical solutions of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0034] like Figure 1 The diagram illustrates the arrangement of photodiodes 11 in the optical receiver 1 provided by this invention. It includes at least two columns of photodiodes 11, with adjacent columns staggered so that one column of photodiodes 11 falls between two adjacent photodiodes 11 in the adjacent column. Further, in the diagram, the inner frame of each photodiode 11 represents its light-receiving area 111, and the outer frame 112 represents its actual package size. In this invention, the light-receiving area 111 of one column of photodiodes 11 is collinear with the light-receiving areas 111 of two adjacent photodiodes 11 in the adjacent column. In this structure, there are no gaps between the light-receiving areas 111 of the photodiodes 11, allowing the optical receiver 1 to identify and determine the specific location of the signal regardless of where the laser light is irradiated. Furthermore, because each photodiode 11 is an independent unit, the blind zone is extremely small, resulting in more accurate location determination and preventing missed detections.

[0035] like Figure 2 As shown, the optical receiver 1 provided by the present invention performs the detection according to the following steps:

[0036] (1) Calibrate the height range of the photodiode;

[0037] Fix the light receiver 1 on a standard height ruler, and use a standard light source to emit light at the center position of the nth photodiode. Mark the center points of the two adjacent photodiodes of the nth photodiode, that is, mark the center position of the (n-1)th photodiode as point A, and mark the center position of the (n+1)th photodiode as point C. Amplify the signal through a transimpedance amplifier circuit and convert the light signals at points A and C into electrical signals. Record the amplitude of the electrical signals at points A and C as V. a and V c The signal ratio X is calculated according to equation (1):

[0038]

[0039] When X = 0, the position at this time is marked as the center position of the nth photodiode, denoted as X0.

[0040] Move the standard height gauge upwards by 1 mm, and calculate the signal ratio between points A and C according to formula (1), denoted as X. -1 Continue moving upwards by 1mm, and calculate the signal ratio between points A and C again according to equation (1), denoted as X. -2 ; and so on, forming the calibration range below the center position of the nth photodiode: X -1 X -2 X -3 , ..., X -m Where m satisfies:

[0041]

[0042] L is the light-receiving length of the light-receiving region of the photodiode, expressed in equation (2) as m is no more than The largest integer.

[0043] Similarly, after resetting the standard height gauge, move it downwards by 1mm, and calculate the signal ratio between points A and C according to formula (1), denoted as X. +1 Continue moving upwards by 1mm, and calculate the signal ratio between points A and C again according to equation (1), denoted as X. +2 ; and so on, forming the calibration range above the center position of the nth photodiode: X +1 X +2 X +3 , ..., X +m Where m satisfies equation (2).

[0044] (3) Detect and calculate the position of the laser beam;

[0045] A laser beam is projected onto the optical receiver 1 using a laser line projector. Each photodiode in the optical receiver 1 receives the laser signal, which is then amplified and converted into an electrical signal by a transimpedance amplifier circuit. The amplitude of the electrical signal from each photodiode is recorded sequentially as V1, V2, V3…V… e Where e is the total number of photodiodes in the light receiver 1. And V1 to V2 are determined. e The maximum value V in f The position D of the laser beam is calculated and determined according to equation (3):

[0046]

[0047] Where f represents the number of the photodiode corresponding to the maximum amplitude of the electrical signal;

[0048] L represents the light-receiving length of the light-receiving area of ​​each photodiode.

[0049] Then, the relative position H of the laser beam is calculated and determined according to equations (4) and (5):

[0050] H = D - (f - 1) × K Equation (4)

[0051]

[0052] when At that time, the laser beam is located at the center of the f-th photodiode;

[0053] when At that time, the laser beam was positioned above the f-th photodiode, and then X... f The height range X specified in step (2) +1 X +2 X +3 ..., X +m By comparing these measurements, the exact position of the laser beam can be obtained, accurate to 1mm.

[0054] when At that time, the laser beam was positioned below the f-th photodiode, and then X... f The height range X specified in step (2) -1 X -2 X -3 ..., X -m By comparing these measurements, the exact position of the laser beam can be obtained, accurate to 1mm.

[0055] The above detection method enables the optical receiver 1 to accurately determine the position of the laser beam, and the coordinates of the position can be accurate to 1mm.

[0056] The optical receiver 1 provided by the present invention can be used in an optical receiving sensor, which is used in conjunction with a laser line projector.

[0057] Although the present invention has been disclosed above by way of embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for detecting an optical receiver, characterized in that, The light receiver includes at least two columns of photodiodes, with adjacent columns of photodiodes staggered from each other. The light-receiving area of ​​one column of photodiodes coincides linearly with the light-receiving areas of the two adjacent photodiodes in the adjacent column. Detection is performed according to the following steps: (1) Calibrate the height range of the photodiode; Fix the light receiver on a standard height ruler, use a standard light source to align with the center position of the nth photodiode, and calculate the ratio of the electrical signal amplitude at the center positions of the (n+1)th and (n-1)th photodiodes respectively; Starting from the center position of the nth photodiode, move the standard height ruler up and down respectively, and record the ratio of the electrical signal amplitude at the center positions of the (n+1)th and (n-1)th photodiodes to form a calibration range; (2) Detect and calculate the position of the laser beam; The laser beam is projected onto the optical receiver, and the electrical signal amplitude of each photodiode is recorded. The maximum electrical signal amplitude is determined, and the position of the laser beam is calculated. Based on the calibration range in step (1), the relative position of the laser beam on the optical receiver is determined. The method for calculating the relative position of the laser beam on the optical receiver is as follows: X f V is the ratio of the electrical signal amplitude at the center position of the f-th photodiode. f+1 V is the electrical signal amplitude at the center position of the (f+1)th photodiode. f−1 Let f be the electrical signal amplitude at the center position of the (f-1)th photodiode, f be the number of the photodiode corresponding to the maximum electrical signal amplitude, and D be the position of the laser beam. When H=L / 2, the position of the laser beam is located at the center of the f-th photodiode, where L is the light-receiving length of the photodiode; When 0<H<L / 2, the position of the laser light is located at the upper position of the f-th photodiode, and then X f is compared with the calibration value range calibrated in step (1); When L / 2<H<L, the position of the laser light is located at the lower position of the f-th photodiode, and then X f is compared with the calibration value range calibrated in step (1).

2. The optical receiver detection method according to claim 1, characterized in that, The method for determining the ratio of the electrical signal amplitude at the center position of the (n+1)th and (n-1)th photodiodes in step (1) is as follows: Va is the electrical signal amplitude at the center position of the (n-1)th photodiode, and Vc is the electrical signal amplitude at the center position of the (n+1)th photodiode.

3. The optical receiver detection method according to claim 1, characterized in that, In step (1), the standard height gauge moves by 1 mm each time, moving up and down m times respectively, where m is the largest integer not exceeding L / 2, and L is the light-receiving length of the photodiode.

4. The optical receiver detection method according to claim 3, characterized in that, The method for calculating the position of the laser beam in step (2) is as follows: In the formula, f is the number of the photodiode corresponding to the maximum amplitude of the electrical signal, and L is the light-receiving length of the photodiode.

5. A light receiving sensor, comprising a light receiver, the light receiver comprising at least two columns of photodiodes, the photodiodes in adjacent columns being staggered relative to each other, and the light-receiving area of ​​one column of photodiodes being collinear with the light-receiving areas of two adjacent photodiodes in the adjacent column, characterized in that, The optical receiver detects the position of the laser beam according to the detection method described in any one of claims 1 to 4.

6. A laser line projector, characterized in that, It is used in conjunction with the optical receiving sensor as described in claim 5.

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