CN115903212A - A laser display optical machine beam combining debugging method and testing equipment - Google Patents

Abstract

The application discloses a laser display optical machine beam combining debugging method and testing equipment. When this method is debugged, the components are adjusted so that the distance between the light outlet of the product and the target surface of the camera reaches a preset distance, and the preset distance is equal to the actual working distance during product design. The light emitted by one laser beam is combined and defocused, and the spot falls on the target surface, and the size of the spot is adjusted to the preset size, and the camera captures the spot. Then use this light spot as the reference light spot, adjust the light spots emitted by the lasers of other channels to align with the reference light spot in turn, until the debugging is completed. In this way, the standard of beam combination can be quantified, the quality of beam combination can be improved, and the picture quality of scanning display can be improved.

Description

A laser display optical machine beam combining debugging method and testing equipment

technical field

The present application relates to the technical field of laser scanning, in particular to a beam combining debugging method and testing equipment in a laser display optical machine.

Background technique

The laser beam scanning display technology is becoming more and more mature, which utilizes the good directionality of the laser. As disclosed in US20080225366A1 and US20120257262A1, the direction of the laser beam is dynamically changed by a scanning device (vibrating mirror, scanning mirror, etc.), so that it scans on the screen to form a picture. This technology does not require complex optical components, the structure can be greatly simplified, and the light utilization efficiency is greatly increased. Due to these advantages, laser beam scanning display technology is considered to have broad application prospects in the field of microdisplays. However, in the manufacturing process of the laser scanning display optical machine, the light source part generally uses multiple visible light lasers with different wavelengths to form a beam of light through a customized optical path, and scans on the screen through the scanning device to form a picture. The quality of the combined beam spot and the degree of spot overlap will greatly affect the final quality of the scanning display.

Contents of the invention

In order to overcome the above disadvantages, the purpose of this application is to provide a method for debugging beam combination in a laser display optical machine, which can improve the quality of beam combination.

In order to achieve the above object, the technical scheme adopted by the application is:

A beam combining debugging method of a laser optical machine, characterized in that,

The method comprises the steps of:

S1, making the distance between the light outlet of the optical machine and the target surface of the camera reach a preset distance based on the adjustment of the adjusting part;

S2, based on the adjustment module, adjust the light beam emitted by the matching laser in the optical machine so that the light spot of the light beam falling on the camera target surface reaches a pre-designed size, and use this light spot as a reference light spot;

S3, obtain the image information of the reference light spot based on the camera, and feed it back to the data processing unit, and the data processing unit fits the Gaussian function of the upper/lower edge of the reference light spot based on the image information, and determines the left/right edge of the light spot;

S4, calculate the center of the spot, that is, the data processing unit counts all the points whose gray scale is not 0 based on the pixel range of the camera target surface, and takes the horizontal and vertical medians as the center of the spot;

S5, adjusting the matching adjustment modules of the other lasers in turn, so that the light spots falling on the camera target surface are aligned with the reference light spots, until all the lasers are adjusted. Through such a design, the beam combining standard can be quantified and the beam combining quality can be improved. In this embodiment, the optical path of one laser in the optical machine can be triggered, and then other optical paths can be triggered in turn to adjust. It can also be triggered at the same time. After adjusting one of the paths to the reference spot, the rest of the laser light paths will be the reference in turn.

Preferably, this step S3 includes, judging row by row from top to bottom, when the row of pixels continuously appears high-gray-scale pixel points, it is recorded as the upper edge coordinate y1 of the reference spot,

Judging row by row from bottom to top, when the row of pixels continuously appears high-grayscale pixels, it is recorded as the lower edge coordinates of the reference spot,

And fit the Gaussian function of the upper/lower edge of the reference spot

When the light intensity is at the maximum value of 1/e, locate the left/right edge of the reference spot, which are recorded as x1 and x2 respectively.

Preferably, the step S5 includes: when the difference between the size of the light spot emitted by the other lasers and the reference light spot is within a preset threshold, it is determined as a coincident position. The threshold is between 3 and 10%. Such as 3%, 5%, 10%.

Preferably, the step S2 also includes adding an attenuation sheet, and the attenuation sheet is used to reduce the intensity of the light spot.

Preferably, the S2 reference spot is a Gaussian spot.

Preferably, in this step S2, based on the adjustment module, the light spot of the light beam falling on the target surface of the camera is adjusted to a pre-designed size by way of defocus adjustment.

Preferably, before step S1, it also includes placing the optical machine to be tested on the stage. The stage can be configured on a movable guide rail. In other embodiments, the stage is fixed on the base of the testing device.

Preferably, the calculation of the spot center in S4 includes:

为光斑中心；Count all the points whose gray level is not 0 within the range of pixels x ₁ , x ₂ , y ₁ , and y ₂ on the camera target surface, and record the total number as s, and the pixel points

is the spot center;

Take all the continuous points whose gray level is not 0 in the pixels of the camera target surface to form an irregular figure, the total number of pixels is recorded as s, and the center of mass of the figure is the spot center.

An embodiment of the present application provides a testing device, which executes the above-mentioned bundle combining debugging method during operation.

Beneficial effect

Compared with the prior art, the optical-mechanical beam combining debugging method proposed in this application quantifies the beam combining standard and improves the beam combining quality.

Description of drawings

FIG. 1 is a schematic structural diagram of a beam combining debugging device according to an embodiment of the present application;

Fig. 2 is a schematic diagram of the beam combining debugging of the laser of the embodiment of the present application;

FIG. 3 is a schematic flow diagram of beam combining debugging according to an embodiment of the present application;

FIG. 4 is a schematic diagram of beam-combined laser spots according to an embodiment of the present application.

Detailed ways

The preferred embodiments of the application will be described in detail below in conjunction with the accompanying drawings, so that the advantages and features of the application can be more easily understood by those skilled in the art, so as to define the protection scope of the application more clearly.

Example

This application discloses a beam combining debugging method of a laser display optical machine. When debugging the beam combining method, the part to be tested (product) is placed on the object stage, and the distance between the light outlet of the product and the target surface of the camera is adjusted by adjusting the parts. To the preset distance, the preset distance is equal to the actual working distance when the product is designed. Based on the adjustment module, the light beam emitted by the matching laser in the optical machine is adjusted, and the light spot falls on the target surface after defocusing, and the size of the light spot is adjusted to a preset size, and the camera shoots the light spot. Then use this spot as the reference spot to adjust the spots emitted by the lasers of other channels in sequence (in order to distinguish the reference spots, the spots emitted by the lasers of other channels can be called adjustment spots.) Align to the reference spot until the debugging is completed. Through such a design, the standard of beam combination can be quantified, the consistency of the product is good, the quality of beam combination is improved, and the picture quality of scanning display is improved. In one embodiment, an angle adjustment component is arranged on the stage, and the angle adjustment component is rotated so that the light outlet of the product is parallel or roughly parallel to the target surface of the camera, which facilitates the camera to obtain clear spot information.

This application proposes a device for beam combining and debugging of laser light machines, which includes:

Adjusting part (also called slide table) 100, the fixing part 400 is arranged on the adjusting part 100, and a plurality of receiving grooves 401 are arranged on the fixing part, and the attenuation pieces are placed in the receiving grooves 401, and one side of the receiving grooves is arranged with A camera 500, the camera is fixed on the adjustment component 100, the camera can be a ccd camera.

The camera is fixed on the adjusting part 100 and a bracket 110 is configured, and the bracket 110 can be used to fix the camera and the fixing part 400 . A hole 402 is arranged in the middle of the fixing part 400, and the combined beam 300 passes through the hole 402 and enters the field of view of the camera 500 after passing through the attenuation sheet, and the camera 500 obtains the light spot information on the target surface.

The side of the receiving tank away from the camera is provided with a stage, and the stage (not shown) is used to place the product 200 to be tested. The optical machine is equipped with multiple channels of visible light lasers with different wavelengths (such as R, G, and B lasers), beam combining optical paths, and defocus/coupling optical paths. Next, beam adjustment will be described in conjunction with Figure 2.

Optical machine 10 includes:

The first laser 11, the second laser 12, the first laser 13, the defocus adjustment module 14 and the collimator 15, and the defocus adjustment module 14 is arranged in the optical path of the first laser 11, the second laser 12 and the first laser 13 There is a defocus adjustment module 14 in the front, and the light spot after the defocus adjustment is passed through the collimation component 15 and combined beams falls on the target surface (not shown).

During the test, adjust the components so that the distance between the light outlet of the product and the target surface of the camera reaches a preset distance, which is equal to the actual working distance when the product is designed. Then the light emitted by each laser is combined and adjusted sequentially. That is, the light emitted by the laser is collimated and combined, and the spot falls on the target surface, and the size of the spot is adjusted to the preset size through the defocusing action, and the camera captures the spot. Then use this light spot as the reference light spot, adjust the light spots emitted by the lasers of other channels to align with the reference light spot in turn, until the debugging is completed. In this way, the standard of beam combination can be quantified, the quality of beam combination can be improved, and the picture quality of scanning display can be improved. In this embodiment, the attenuation sheet is used to reduce the intensity of the light spot, protect the target surface of the camera, and make the captured image clearer. In this implementation manner, three lasers are taken as an example for description. In other embodiments, there may be 4 lasers (R/G/B/W lasers), or other numbers of lasers.

Next, a debugging method for combining laser beams with the above-mentioned equipment is described, and the method includes the following steps:

S1, adjust the adjusting part so that the distance between the light outlet of the product and the target surface of the camera is preset;

S2, focus the light spot on the camera target plane to a pre-designed size based on the defocus adjustment method;

S3, the target surface is judged line by line according to the preset order (such as from top to bottom), and the Gaussian function of the upper and lower sides of the spot is fitted based on the data processing unit, and the light intensity is at the maximum value 1/e (with the center of the spot The distance is about the standard deviation of the fitted Gaussian function σ) to locate the left and right edges of the spot,

S4, calculate the center of the spot, that is, the data processing unit counts all points with a gray scale within a certain interval based on the pixel range of the camera target surface, and takes the horizontal and vertical medians as the center of the spot, respectively,

S5, sequentially adjust the light spots of each laser to the same x, y by defocusing until the end.

的位置定为重合位置。In one embodiment, in S5 , differences in spot sizes including different optical paths are defined as overlapping positions within a preset range. like

The position is defined as the coincident position.

In one embodiment, S2 includes a moderate attenuation film with additional specifications, which is used to reduce the intensity of the light spot, protect the camera target surface, and make the captured image clearer.

In one embodiment, step S3 includes: judging row by row from top to bottom, when the rows of pixels continuously appear high-gray-scale pixels (to prevent noise pixels from causing misjudgment), record it as the vertical coordinate y ₁ of the upper edge of the light spot, from From bottom to top, y ₂ can be obtained in the same way, and the Gaussian function of the upper and lower sides of the light spot can be obtained by fitting the software of the data processing unit

Locate the left and right edges of the light spot at the point where the light intensity is the maximum value 1/e (the distance from the center of the light spot is about the standard deviation σ of the Gaussian function after fitting), and denote it as x ₁ , x ₂ .

为光斑中心。In one embodiment, step S4 includes: within the range of pixels x ₁ , x ₂ , y ₁ , y ₂ on the camera target surface, count all the pixels whose gray scales are within a certain interval, and record the total number as s, and the pixels

is the spot center.

In one embodiment, step S4 includes: taking all continuous points with gray levels other than 0 in the pixels of the camera target surface to form an irregular pattern, the total number of pixels is denoted as s, and the center of mass of the pattern is the spot center.

The above embodiments are only to illustrate the technical conception and characteristics of the present application. Its purpose is to let those familiar with this technology understand the content of the present application and implement it. It cannot limit the protection scope of the present application. All equivalent changes or modifications should fall within the protection scope of the present application.

Claims (10)

1. A method for adjusting the combined beam of laser optical machine is characterized by that,

the method comprises the following steps:

s1, adjusting the distance between a light outlet of an optical machine and a camera target surface to a preset distance based on an adjusting part;

s2, adjusting a light beam emitted by a laser device in the optical machine, which is matched and corresponding to the adjusting module, based on the adjusting module, so that a light spot of the light beam on the target surface of the camera is within a pre-designed size, and the light spot is taken as a reference light spot;

s3, obtaining image information of the reference light spot based on the camera and feeding the image information back to the data processing unit, wherein the data processing unit fits a Gaussian function of the upper edge and the lower edge of the reference light spot based on the image information and determines the left edge and the right edge of the reference light spot;

s4, calculating the center of the light spot, namely counting all points with the gray scale not being 0 in the pixel range of the target surface of the camera by the data processing unit, and respectively taking the transverse median and the longitudinal median as the center of the reference light spot;

and S5, adjusting the adjusting modules matched with the other lasers in sequence to enable light spots of light beams emitted by the adjusting modules falling on the target surface of the camera to align with the reference light spots until the adjustment of all the lasers is finished.

2. The beam combination debugging method of claim 1, wherein,

the step S3 comprises line-by-line judgment from top to bottom, marking as the coordinate y1 of the upper edge of the reference facula when the pixels of the line continuously generate high gray pixel points,

judging line by line from bottom to top, marking as the lower edge coordinate y2 of the reference facula when the pixels of the line continuously appear high gray pixel points,

and fitting to obtain the Gaussian function of the upper/lower edges of the reference light spot

And (5) positioning the left/right edges of the reference light spot at the position where the light intensity is the maximum value 1/e, and respectively recording the left/right edges as x1 and x2.

3. The beam combination debugging method of claim 1, wherein,

the step S5 comprises the following steps: and when the difference between the sizes of the light spots emitted by the lasers of the other paths and the reference light spot is within a preset threshold value, determining the laser to be the superposition position.

4. The beam combination debugging method of the laser optical bench of claim 3,

the threshold is between 3 and 10%.

5. The beam combination debugging method of claim 1, wherein,

step S2 also comprises adding an attenuation sheet, wherein the attenuation sheet is used for weakening the spot intensity.

6. The beam combination debugging method of the laser optical machine according to claim 1, wherein the reference light spot in the step S2 is a gaussian light spot.

7. The beam combination debugging method of claim 1, wherein,

and in the step S2, the light beam is focused on the light spot of the target surface of the camera to a pre-designed size in a defocusing adjustment mode based on the adjusting module.

8. The method for adjusting the combined beam of the laser optical bench according to claim 1, wherein the step S4 of estimating the center of the reference spot comprises:

at camera target surface pixel x ₁ ，x ₂ ，y ₁ ，y ₂ Counting all the points with the gray scale not 0 in the range, and counting the total number as s and the pixel points

Is the spot center.

9. The beam combination debugging method of claim 1, wherein,

before the step S1, the method further includes placing the optical bench to be tested on an object stage.

10. A test device of a laser optical bench, wherein the test device executes the beam combining debugging method according to any one of claims 1-9 when running.

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