CN111380669A - Light source testing device and light source testing method - Google Patents

Abstract

The application relates to the field of optical testing, in particular to a light source testing device, and discloses a light source testing device which comprises a light source to be tested, a light guide plate, a photoreceptor and a testing circuit, wherein the light source to be tested is used for emitting light; the light guide plate is used for converting incident light into isotropic light; the photoreceptor is used for converting the optical signal into an electric signal; the test circuit is used for measuring the light source parameters according to the electric signals. This application adopts the light guide plate to receive the incident light, becomes the even light of all directions with concentrated light, receives by the photoreceptor of fixing at light guide plate fixed position again. The degree to which the light guide plate uniformly disperses the emitted light is the same for each light source, so that the power scale factor can be determined by calibration, and the peak power can be calculated from the factor. The embodiment of the application has simple structure, and the light guide plate is only required to be placed on the light source light path, so that the light source is not required to be aligned, the operation is simple, and the required adjustment is less.

Description

Light source testing device and light source testing method

Technical Field

The invention relates to the technical field of laser radar testing, in particular to a light source testing device and a testing method.

Background

In laser radar production, in order to improve production efficiency, the module assembly needs to be tested before assembly, and the light source is particularly important to be detected as the core assembly of the laser radar.

Laser radar is used as an emerging industry, a unified method and equipment are not formed in the current test, and the existing equipment is generally partially modified according to parameters to be tested.

The light source involves optics, so the test is relatively complex, and the current test tools mainly comprise a photoelectric probe, an optical power meter and the like. The devices need to align the laser emission light beam for measurement when testing, and as most of the light probes have small light sensing windows, generally smaller than 1mm, all the emission light must be placed in the receiving window during the testing process, otherwise the measured laser peak power is inaccurate. And the larger the window, the more likely ambient light interference will be introduced. Alignment of the test tool during testing becomes the most time consuming process.

Therefore, it is desirable to provide a light source testing device with simple testing operation and less time consumption.

Disclosure of Invention

The embodiment of the application provides a light source testing device, and solves the problems of complex operation and long consumed time in the prior art.

To achieve the purpose, the embodiment of the invention adopts the following technical scheme:

on one hand, a light source testing device comprises a light source to be tested, a light guide plate, a photoreceptor, and a testing circuit,

the light source to be detected is used for emitting light;

the light guide plate is used for converting incident light into isotropic light;

the photoreceptor is used for converting the optical signal into an electric signal;

the test circuit is used for measuring the light source parameters according to the electric signals.

In a possible embodiment, the photoreceptor is arranged on the top, bottom or backlight surface of the light guide plate.

In a possible embodiment, the light source testing device further includes a light guide pillar, and the light guide pillar and the light guide plate are disposed on the same light path and used for guiding incident light to the light guide plate.

In a possible embodiment, the number of the light guide columns is one or more, and the light guide columns correspond to the light sources to be measured one by one.

In one possible embodiment, one end of the light guide pole is in close contact with the light guide pole.

In a possible embodiment, the light guide pillar is made of polymethyl methacrylate, and the light guide plate is made of polymethyl methacrylate, polycarbonate or polystyrene.

In a possible embodiment, the light source to be measured has a lens, and one end of the light guide pillar is matched with the lens, and the diameter of the light guide pillar is larger than that of the light source lens.

In a possible embodiment, the light source to be measured is a laser emitting module or a semiconductor laser.

In a possible embodiment, the photoreceptor is a photodetector or a photodiode or an avalanche photodiode.

In one possible embodiment, the test circuit further comprises a peak detection circuit, a pulse width test circuit, and a high speed AD for detecting the peak power, the pulse width, and the time taken for the intensity of the optical pulse to reach from 10% to 90% of the peak power.

This application embodiment receives the incident light through adopting the light guide plate, becomes the even light of all directions with concentrated light, receives by the photoreceptor of fixing at light guide plate fixed position again. The degree to which the light guide plate uniformly disperses the emitted light is the same for each light source, so that the power scale factor can be determined by calibration, and the peak power can be calculated from the factor.

The embodiment of the application has simple structure, and can be realized by only placing the light guide plate on the light source light path, the operation is simple, and the needed adjustment is few.

Drawings

Fig. 1 is a schematic diagram of an embodiment of the present application.

FIG. 2 is a schematic view of the light guide post according to the embodiment of the present application.

FIG. 3 is a schematic view of the present application with a plurality of light guide posts.

Fig. 4 is a schematic view of a light source to be measured having a lens according to an embodiment of the present application.

In the figure: 1. a light guide plate; 2. a photoreceptor; 3. a test circuit; 4. a light guide pillar; 5. and a light source to be measured.

Detailed Description

The technical scheme of the application is further explained by the specific implementation mode in combination with the attached drawings.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the application described herein may be used. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, apparatus, article, or device that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or device.

The embodiment of the application.

As shown in fig. 1, a light source testing apparatus includes a light source 5 to be tested, a light guide plate 1, a photoreceptor 2, and a testing circuit 3, where the light source 5 to be tested is used to emit light; the light guide plate 1 is used for converting incident light into isotropic light; the photoreceptor 2 is used for converting optical signals into electric signals; the test circuit 3 is used for measuring the light source parameters according to the electric signals. The light guide plate 1 is a PMMA light guide plate, and a (PS) light guide plate or a Polycarbonate (PC) light guide plate can be selected as required. The photoreceptor 2 is a photoelectric probe or a photodiode or an avalanche photodiode.

The light guide plate 1 is used for receiving incident light, concentrated light is changed into light with uniform directions, and the light is received by the photoreceptor 2 fixed at a fixed position of the light guide plate 1. The degree of uniform dispersion of the emitted light by the light guide plate 1 is the same for each light source, so that the ratio of the light received by the photoreceptor to the total incident light power can be determined by experimental calibration, and the peak power can be calculated according to the ratio. The experiment calibration is that a light source with fixed power is adopted to irradiate the light guide plate 1, the photoreceptor 2 obtains a measured power, and the ratio of the measured power to the fixed power is the proportion of part of light received by the photoreceptor to the whole incident light power.

The photoreceptor 2 is arranged at the top, the bottom or the backlight surface of the light guide plate 1.

The photoreceptor 2 may be disposed on any side of the light guide plate except the receiving surface.

As shown in fig. 2, the light source testing device may further include a light guide column 4, where the light guide column 4 and the light guide plate 1 are disposed on the same light path, and are used for guiding incident light to the light guide plate 1.

The light guide post 4 is provided to guide all incident light to the light guide plate, thereby reducing light loss. If the direct illumination is possible, the light spot is scattered and a part of the light is not received by the light guide plate 1.

As shown in fig. 3, sometimes a plurality of light sources need to be measured simultaneously, a plurality of light guide columns 4 may be provided, and the plurality of light guide columns 4 correspond to the plurality of light sources 5 to be measured.

Because the effect of light guide plate 1, the luminescence of every light source 5 that awaits measuring is by the homodisperse, consequently also does not have strict requirement to the position of light source 5 that awaits measuring on light guide plate 1, consequently can place a plurality of leaded light posts 4 on a light guide plate 1, to test a plurality of light sources 5 that await measuring, test circuit 3 triggers every light source 5 that awaits measuring in proper order and gives out light during the test to obtain the signal from photoreceptor 2, and then the parameter of handling calculation every light source that awaits measuring. The method is used for testing the laser module PCBA which is welded but not separated in mass production.

One end of the light guide column is in close contact with the light guide plate, so that light is prevented from diffusing from the gap, and the measurement result is not accurate.

The light guide column is made of polymethyl methacrylate, and the light guide plate is made of polymethyl methacrylate, polycarbonate or polystyrene.

As shown in fig. 4, it is sometimes necessary to perform inspection of the light source 5 to be inspected with an optical system. The optical system comprises a lens 6 and a lens barrel 5 for placing the lens 6, wherein one end of the light guide column 4 is matched with the lens 6, and the diameter of the light guide column is larger than that of the lens 6.

The diameter of the light guide column 4 is larger than or equal to the diameter of the lens 6, so that all emitted light can be guided into the light guide plate 1 as much as possible, and the light guide column is matched with the lens 6 and is attached to the curvature to reduce light reflection in the gap. And for the emission module which is qualified in the test of the non-optical system, the emission module is tested again after the optical system is added, so that a defective product in the optical system can be found.

In order to improve the detection efficiency, a plurality of light guide columns 4 can be disposed on one light guide plate 1 to test a plurality of light sources 5 to be tested with optical systems. During testing, the test circuit sequentially triggers each light source 5 to be tested to emit light, receives signals of the photoreceptors 2, processes and calculates parameters of the light source to be tested after the optical system is added, and finds problems.

The photoreceptor is a photoelectric probe or a photodiode or an avalanche photodiode.

The test circuit also comprises a peak detection circuit, a pulse width test circuit and a high-speed AD, and is used for detecting the peak power, the pulse width and the time for the light pulse intensity to reach from 10% to 90% of the peak power.

The peak detection circuit, the pulse width test circuit and the high-speed AD are all in the prior art.

The technical principles of the present application have been described above in connection with specific embodiments. The description is made for the purpose of illustrating the principles of the present application and is not to be construed in any way as limiting the scope of the application. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present application without inventive effort, which shall fall within the scope of the present application.

Claims (10)

1. A light source testing device is characterized in that the device comprises a light source to be tested, a light guide plate, a photoreceptor and a testing circuit,

the light source to be detected is used for emitting light;

the light guide plate is used for converting incident light into isotropic light;

the photoreceptor is used for converting the optical signal into an electric signal;

the test circuit is used for measuring the light source parameters according to the electric signals.

2. The apparatus for testing light source of claim 1, wherein the light sensor is disposed on the top, bottom or back side of the light guide plate.

3. The light source testing device of claim 1 or 2, further comprising a light guide pillar disposed on the same optical path as the light guide plate for guiding the incident light to the light guide plate.

4. The light source testing device of claim 3, wherein the number of the light guiding columns is one or more, and the light guiding columns correspond to the light sources to be tested one by one.

5. The light source testing device of claim 4, wherein one end of the light guide pillar is in close contact with the light guide plate.

6. The light source testing device of claim 5, wherein the light guide pillar is made of polymethyl methacrylate, and the light guide plate is made of polymethyl methacrylate, polycarbonate or polystyrene.

7. The apparatus as claimed in claim 6, wherein the light source to be tested has a lens, and one end of the light guide rod is matched with the lens and has a diameter larger than that of the lens of the light source.

8. The light source testing device of claim 7, wherein the light source to be tested is a laser emitting module or a semiconductor laser.

9. The light source testing device of claim 8, wherein the light sensor is a photo probe or a photodiode or an avalanche photodiode.

10. The light source testing device of claim 1, wherein the testing circuit further comprises a peak detection circuit, a pulse width testing circuit, a high speed AD for detecting peak power, pulse width and time taken for the light pulse intensity to be from 10% to 90% of peak power.

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