CN115165089B - Rectangular uniform sheet light source debugging method and device - Google Patents

Abstract

The invention provides a method and device for debugging a rectangular uniform light source, which detects the optical power of sub-lasers through a densely packed detection surface of sensor units, and converts the elliptical area illuminated by a single or multiple sub-lasers on the detection surface into a corresponding elliptical area with A rectangle of relative width and length, and divided into multiple sub-power areas according to the heat absorbed by the illuminated area. Each sub-power area displays the average power. The average power is represented by numbers and block areas of different colors. By the numbers and colors displayed Adjust the sub-laser and optical system. The invention can humanely display the relative width, length and power of a single or multiple sub-lasers in the illuminated area of the detection surface, improves the operator's convenience in the light source adjustment process, and realizes rapid adjustment of the uniformity of the rectangular light source.

Description

A method and device for debugging a rectangular uniform light source

Technical field

The invention relates to the field of optical technology, and in particular to a method and device for debugging a rectangular uniform light source.

Background technique

Planar Laser Induced Fluorescence (PLIF) is an optical detection technology widely used in scalar field measurement in fluids. Its principle is to excite certain components in the fluid to emit fluorescence through laser excitation, and obtain the information by detecting the distribution of fluorescence intensity. Characteristic scalar field (concentration field, temperature field or pH field) within the range to be measured.

PLIF measurement requires the use of a plane laser as the induced laser sheet light source. In traditional technology, cylindrical mirrors are usually used to expand a single laser beam. However, due to the uneven cross-sectional energy distribution of the laser beam itself, the use of cylindrical mirror beam expansion can only spatially expand the laser beam into a light source, but cannot change the light intensity distribution. Although the Powell prism can improve the light intensity distribution of the sheet light source to a certain extent, the center light intensity of the sheet light source obtained by using the Powell prism is weaker than the two sides. The light intensity uniformity generally does not exceed 70%, and the high uniformity optical path is shorter. . Therefore, the above method still has the problem of uneven light intensity distribution.

Patent CN111579485A proposes a uniform sheet light source system using multiple (more than 5) sub-lasers side by side. This system provides a better idea for the development of uniform sheet light sources. However, when the number of sub-lasers is large (more than 10), adjusting the light intensity uniformity of the rectangular laser sheet light source in actual application is a time-consuming and laborious task. This is because adjusting the laser uniformity requires relying on a laser power meter to detect the sheet. Uniformity of the light source, but currently most laser power meters use single-point testing methods. If the measurement points are too dense, the debugging process will be too long. If the measurement points are too few, the uniformity of the light source cannot be guaranteed.

Contents of the invention

The purpose of the present invention is to provide a solution that can quickly adjust the uniformity of a sheet light source in view of the deficiencies in the above background technology.

In order to achieve the above purpose, the present invention provides a method for debugging a rectangular uniform light source, which detects the optical power of sub-lasers through the detection surface of densely distributed sensor units, and converts the elliptical area illuminated by single or multiple sub-lasers on the detection surface into corresponding A rectangle with relative width and length, and is divided into multiple sub-power areas according to the heat absorbed by the illuminated area. Each sub-power area displays the average power. The size of the average power is represented by different colors and/or numbers. Through the displayed power Adjust the sub-laser and optical system.

Furthermore, the greater the power, the darker the color of the block area represented.

Further, the detection surface is also set in a rectangular shape.

Further, the area of the sub-power region is adjustable.

Further, the minimum area of the sub-power area includes at least one sensor unit.

Further, adjusting the sub-laser and the optical system includes power adjustment of the sub-laser and position adjustment of the optical system.

The invention also provides a rectangular uniform light source debugging device, which adopts the method as mentioned above and includes a rectangular laser power detector, a power display and a signal transmission line. The rectangular laser power detector communicates with the signal transmission line through the signal transmission line. Power monitor connection;

The rectangular laser power detector has a rectangular detection surface, and a plurality of sensor units are densely covered on the detection surface. The sensor units transmit the detected optical power signal to a power display, and the power display can display single or multiple sub-pixels. The laser illuminates the relative width and length of the area on the detection surface, and divides the rectangular diagram into multiple sub-power areas based on the power absorbed by the illuminated area, which is represented by different colors and/or numbers based on the average power.

The above solution of the present invention has the following beneficial effects:

The method and device for debugging a rectangular uniform light source provided by the present invention can display the relative width and length of the area illuminated by a single or multiple sub-lasers on the detection surface, and divide the rectangular diagram on the power display into multiple sections based on the heat absorbed by the illuminated area. The sub-power area is represented by different colors and numbers according to the average power of the area, allowing the operator to adjust the power of multiple sub-lasers and the position of the optical system according to the position and color of the rectangular diagram on the power display, which improves light source adjustment. The convenience enables quick adjustment of the uniformity of the rectangular light source;

Other beneficial effects of the present invention will be described in detail in the subsequent detailed description.

Description of the drawings

Figure 1 is a schematic structural diagram of a rectangular light source in the present invention;

Figure 2 is a schematic diagram of the Gaussian distribution of light intensity of a single laser light source in the present invention;

Figure 3 is a schematic diagram of a single laser light source in the present invention;

Figure 4 is a schematic diagram of single laser power conversion in the present invention;

Figure 5 is a schematic diagram of the adjustment process of the rectangular light source in the present invention.

Detailed ways

In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, a detailed description will be given below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention. In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limitations of the invention. Furthermore, the terms “first”, “second” and “third” are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, for the sake of simplicity, the method or rule is depicted or described as a series of operations, and the purpose is neither to exhaust the experimental operations nor to limit the order of the experimental operations. For example, experimental operations may be performed in various orders and/or simultaneously, and include other experimental operations again not described. Furthermore, not all of the steps described are required for the methods and algorithms described herein. Those skilled in the art will recognize and understand that these methods and algorithms can be represented as a series of unrelated states through state diagrams or projects.

Embodiments of the present invention provide a method for debugging a rectangular uniform light source. The rectangular light source is composed of multiple sub-lasers, as shown in Figure 1. Including multiple sub-lasers and multiple optical systems. Sub-lasers are used to generate and emit laser beams. The laser beams have the same wavelength and the cross-sectional energy distribution is Gaussian or quasi-Gaussian. The light exit ports of multiple sub-lasers are located in the same plane and arranged at equal intervals. The connection lines of the light exit ports are perpendicular to The exit direction of the laser beam. Multiple optical systems correspond to multiple sub-lasers in a one-to-one manner. Each optical system is set on the optical path of the laser beam emitted by its corresponding sub-laser and is used to shape the laser beam to form a sub-sector beam. Assume that a plane laser is formed by superposition in the area, in which the beam expansion angle and thickness of the sub-sector beams are the same.

It can be understood that under ideal conditions, multiple sub-lasers generate and emit laser beams of the same wavelength, that is, the laser beams emitted by multiple sub-lasers have the same wavelength, which can ensure that the frequency of the sub-sector beam corresponding to each sub-laser is the same, thereby ensuring that the final planar laser is formed. uniformity.

However, in practical applications, the initial laser beam parameters of the sub-laser have deviations, and the positions of the sub-lasers and optical systems also have deviations. Especially when there are many sub-lasers and corresponding optical systems, the generated rectangular light source is no longer uniform and cannot be To achieve the corresponding purpose of use, it needs to be debugged.

For the above-mentioned rectangular piece light source, the debugging device used in the present invention includes a rectangular laser power detector, a power display and a signal transmission line. The rectangular laser power detector is connected to the power display through the signal transmission line.

Among them, the rectangular laser power detector has a rectangular detection surface. After the detection surface of the rectangular laser power detector is illuminated by a single or multiple sub-lasers, the sensor units distributed on the detection surface transmit the signal to the power display (the same principle as a conventional power meter , no need to go into details about the principle of photoelectric conversion), the power display can display the relative width and length of the area illuminated by a single or multiple sub-lasers on the detection surface, and divide the rectangular diagram on the power display into multiple sub-lasers according to the heat absorbed by the illuminated area. The power area is represented by different colors and numbers according to the average power of the area. The operator can adjust the power of multiple sub-lasers, the position of the optical system, etc. according to the position and color of the rectangular diagram on the power display, thereby achieving rapid adjustment of the uniformity of the rectangular light source.

Compared with the traditional single-point detection and debugging method, this method can not only display the power on the rectangular detection surface and express it in each block area, but also calculate the standard deviation of the laser power in each block area, etc., helping the operator to quickly modulate a uniform rectangular piece of light source.

As a further explanation, before the laser sheet light source is evenly adjusted, the effect of each sub-laser irradiation may be as shown in Figure 5-a. This method proposes a method based on the currently known light source characteristics of a single laser, such as the Gaussian distribution of light intensity of a single laser source (as shown in Figure 2) and the illumination effect of a single laser source (as shown in Figure 3), as well as the measurement principle of a laser power meter. Rectangular laser power detector, when multiple laser light sources illuminate the detection surface of the rectangular laser power detector, the sensor unit on the detection surface converts a certain irradiation area into an equivalent rectangle and displays it on the power display (as shown in Figure 5-b ), the rectangle is divided into multiple sub-areas according to the detected heat. Each sub-area displays the average power of the area. According to the light intensity distribution characteristics of a single laser source (Figure 4), it can be seen that these sub-areas are symmetrical about the laser axis, and the power of the sub-area The distribution is p-n, ..p-2, p-1, p1, p2, pn. These sub-areas are divided into colors of different depths according to the size of the power, helping the operator to observe the difference in power more easily. Then the operator can adjust the optical system of the sub-laser according to the relative position of each rectangular area in Figure 5-b, and can adjust the power of the sub-laser according to the color depth of each area. When the rectangle on the display is shown in Figure 5 After -b is adjusted to 5-c, the adjustment of the rectangular light source can be completed. The final rectangular light source with good uniformity is shown in Figure 5-d.

Preferably, when the power is greater, a darker color display can be used, which is beneficial to the operator's observation of the power distribution.

It should be noted that the more rectangular sub-areas divided into the power display, the more detailed and clear the power display will be. Since the minimum area of the sub-power region includes at least one sensor unit, it can be understood that when the sensor units on the detection surface of the rectangular laser power detector are more densely distributed, the detection accuracy of the rectangular laser power detector is higher, which is more conducive to the operator's rapid Adjust the rectangular piece of light source evenly.

After debugging the rectangular uniform sheet light source using the method provided in this embodiment, the rectangular uniform sheet light source can be packaged in a box-shaped structure and used as a planar laser source for PLIF measurements.

Based on the same inventive concept, this embodiment also provides a rectangular uniform light source debugging device, which includes a rectangular laser power detector, a power display and a signal transmission line. The rectangular laser power detector is connected to the power display through the signal transmission line.

Among them, the rectangular laser power detector has a rectangular detection surface, and multiple sensor units are densely covered on the detection surface. The sensor units transmit the detected optical power signal to the power display. The power display can display the illumination of single or multiple sub-lasers on the detection surface. The relative width and length of the area, and the rectangular diagram is divided into multiple sub-power areas according to the heat absorbed by the illuminated area, which are represented by different colors according to the average power.

Among them, the area of the sub-power area that the power display can display is adjustable. To ensure the rationality of the display, the minimum area of the sub-power area should include at least one sensor unit. When the sub-power area includes only one sensor unit, the power displayed is the optical power detected by the sensor unit. The minimum area of the sub-power area preferably includes four sensor units, so that the power displayed in the area can be averaged by the measured values of multiple sensor units to improve accuracy.

Of course, the number of sensor units is not always better. Too many sensor units increase the difficulty of processing and manufacturing of rectangular laser power detectors, as well as the reliability of heat dissipation.

The above is the preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications can also be made. should be regarded as the protection scope of the present invention.

Claims (6)

1. A method for debugging a rectangular uniform light source, which is characterized in that the optical power of the sub-lasers is detected by densely covering the detection surface of the sensor unit, and the elliptical area illuminated by the multiple sub-lasers on the detection surface is converted into a corresponding elliptical area with relative width , length of a rectangle, and is divided into multiple sub-power areas according to the heat absorbed by the illuminated area. Each sub-power area displays the average power. The average power is represented by a number and/or a block area of different colors. The displayed power is related to the sub-power area. Adjust the laser and optical system; Adjusting the sub-laser and optical system includes power adjustment of the sub-laser and position adjustment of the optical system. When multiple laser light sources illuminate the detection surface of the rectangular laser power detector, the sensor unit on the detection surface converts a certain irradiation area into equal An effective rectangle is displayed on the power display. The operator adjusts the optical system of the sub-laser according to the relative position of each rectangular area, and adjusts the power of the sub-laser according to the color depth of each area until the light source of the rectangular sheet is uniform. 2. A method for debugging a rectangular uniform light source according to claim 1, characterized in that the greater the power, the darker the color of the block area represented. 3. A method for debugging a rectangular uniform light source according to claim 1, characterized in that the detection surface is also set in a rectangular shape. 4. A method for debugging a rectangular uniform light source according to claim 1, characterized in that the area of the sub-power region is adjustable. 5. A method for debugging a rectangular uniform light source according to claim 1, wherein the minimum area of the sub-power region includes at least one sensor unit. 6. A rectangular uniform light source debugging device, using the method according to any one of claims 1 to 5, characterized in that it includes a rectangular laser power detector, a power display and a signal transmission line, and the rectangular laser power detector Connected to the power display through the signal transmission line; The rectangular laser power detector has a rectangular detection surface, and a plurality of sensor units are densely covered on the detection surface. The sensor units transmit the detected optical power signal to a power display, and the power display can detect single or multiple sub-units. The elliptical area illuminated by the laser on the detection surface is converted into a corresponding rectangle with relative width and length, and the rectangular diagram is divided into multiple sub-power areas according to the heat absorbed by the illuminated area, and different colors and/or are used according to the average power. or numerical representation.