Short pulse laser testing device and testing method thereof

Abstract

The invention relates to a short pulse laser testing device and a testing method thereof.The whole testing device comprises a driving circuit, a first photoelectric receiving assembly, a second photoelectric receiving assembly and an upper computer, a to-be-tested laser chip is driven by the driving circuit to emit light, the upper computer recognizes the type of a parameter needing to be measured, and if the type of the parameter needing to be measured is pulse width, the laser chip needs to be tested; if so, starting a first photoelectric receiving assembly to collect light emitted by the to-be-detected laser chip under the driving of the driving circuit; if the type of the required measurement parameter is power, starting a second photoelectric receiving assembly to collect light emitted by the laser chip to be measured under the driving of the driving circuit; the upper computer tests the to-be-tested laser chip according to photoelectric signals collected by the first photoelectric receiving assembly or the second photoelectric receiving assembly. According to the whole device, different photoelectric receiving assemblies are selected based on different test parameter types to collect photoelectric signals, the test accuracy is ensured, and therefore accurate short pulse laser test can be achieved.

Description

Technical Field

[0001] The present application relates to the field of laser testing technology, and in particular to a short pulse laser testing device and a testing method thereof. Background Art

[0002] Traditional laser test benches are mainly based on CW (Continuous Wave) and long pulses (pulses of microseconds and above), and there are few test methods for short pulses with controllable and stable nanosecond levels.

[0003] Stable generation of nanosecond optical pulses requires a high-precision signal generator to control the pulse signal, that is, a nanosecond pulse generator is used to trigger and shut down the signal to emit nanosecond optical pulses. It is even more difficult to perform stable measurements based on the difficulty of stably generating nanosecond optical pulses.

[0004] On the demand side of actual application scenarios, current laser chips need to undergo a lot of thorough testing. Traditional testing platforms cannot accurately test laser chips. Summary of the invention

[0005] Based on this, it is necessary to provide an accurate short pulse laser testing device and a testing method thereof to address the above technical issues.

[0006] In a first aspect, the present application provides a short pulse laser testing device. The device includes a driving circuit, a first photoelectric receiving component, a second photoelectric receiving component, and a host computer;

[0007] The driving circuit is connected to the laser chip to be tested, and the host computer identifies the type of required measurement parameters. If the required measurement parameter type is pulse width, the first photoelectric receiving component is started to collect light emitted by the laser chip to be tested under the driving of the driving circuit; if the required measurement parameter type is power, the second photoelectric receiving component is started to collect light emitted by the laser chip to be tested under the driving of the driving circuit; the host computer tests the laser chip to be tested according to the photoelectric signal collected by the first photoelectric receiving component or the second photoelectric receiving component.

[0008] In one embodiment, the first photoelectric receiving component includes a PD, and the second photoelectric receiving component includes an integrating sphere.

[0009] In one of the embodiments, the first optoelectronic receiving component includes a PD and an optical mode field regulating component, and the optical mode field regulating component is disposed on a receiving surface of the PD.

[0010] In one embodiment, the optical mode field adjustment component includes a first diffuser or a concave lens; or, the optical mode field adjustment component includes a second diffuser or a light attenuation plate.

[0011] In one embodiment, the second photoelectric receiving component includes an integrating sphere or a polarizing plate.

[0012] In one embodiment, the short pulse laser testing device further includes a signal generator, which is connected to the driving circuit and configured to output an adjustment signal to the driving circuit so that the driving circuit adjusts the frequency or pulse width of the laser chip to be tested.

[0013] In one embodiment, the driving circuit includes a charging module, a capacitor and a switch tube;

[0014] The charging module is connected to the capacitor, the capacitor is connected to the input end of the laser chip to be tested, the output end of the laser chip to be tested is connected to the input end of the switch tube, the output end of the switch tube is grounded, and the control end of the switch tube receives an external control signal.

[0015] In one embodiment, the short pulse laser testing device further includes an oscilloscope, and the oscilloscope is connected to the first photoelectric receiving component.

[0016] In one embodiment, the short pulse laser testing device further includes a temperature control component, which is connected to the host computer and is used to adjust the ambient temperature of the laser chip to be tested.

[0017] In a second aspect, the present application also provides a testing method for the above-mentioned short pulse laser testing device. The method comprises:

[0018] In response to initiating a test operation, identifying a desired test parameter type;

[0019] If the required measurement parameter type is pulse width, the first photoelectric receiving component is started to collect the light emitted by the laser chip to be measured under the drive of the drive circuit;

[0020] If the required measurement parameter type is power, the second photoelectric receiving component is started to collect the light emitted by the laser chip to be measured under the drive of the drive circuit;

[0021] The laser chip to be tested is tested according to the collected photoelectric signals.

[0022] The above-mentioned short pulse laser test device and test method thereof, the whole test device includes a driving circuit, a first photoelectric receiving component, a second photoelectric receiving component, and a host computer. The laser chip to be tested emits light under the drive of the driving circuit. The host computer identifies the required measurement parameter type. If the required measurement parameter type is pulse width, the first photoelectric receiving component is started to collect the light emitted by the laser chip to be tested under the drive of the driving circuit; if the required measurement parameter type is power, the second photoelectric receiving component is started to collect the light emitted by the laser chip to be tested under the drive of the driving circuit; the host computer tests the laser chip to be tested according to the photoelectric signal collected by the first photoelectric receiving component or the second photoelectric receiving component. The whole device selects different photoelectric receiving components to collect photoelectric signals based on different test parameter types, ensuring the accuracy of the test, so it can achieve accurate short pulse laser testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structure of a short pulse laser testing device in one embodiment;

[0024] Figure 2 is a schematic structural diagram of a first photoelectric receiving component in an embodiment;

[0025] Figure 3 is a schematic structural diagram of a second photoelectric receiving component in one embodiment;

[0026] Figure 4 It is a schematic structural diagram of a short pulse laser testing device in another embodiment;

[0027] Figure 5 is a schematic structural diagram of a driving circuit in one embodiment;

[0028] Figure 6 It is a schematic diagram of the structure of a short pulse laser testing device in an application example;

[0029] Figure 7 The figure is a flow chart of a testing method of a short pulse laser testing device in one embodiment. DETAILED DESCRIPTION

[0030] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0032] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0033] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0034] When used herein, the singular forms "a", "an" and " / the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0035] In one embodiment, Figure 1 As shown, the present application provides a short pulse laser testing device. The device includes a driving circuit 100, a first photoelectric receiving component 200, a second photoelectric receiving component 300, and a host computer 400;

[0036] The driving circuit 100 is connected to the laser chip to be tested, and the host computer 400 identifies the required measurement parameter type. If the required measurement parameter type is pulse width, the first photoelectric receiving component 200 is started to collect the light emitted by the laser chip to be tested under the drive of the driving circuit 100; if the required measurement parameter type is power, the second photoelectric receiving component 300 is started to collect the light emitted by the laser chip to be tested under the drive of the driving circuit 100; the host computer 400 tests the laser chip to be tested according to the photoelectric signal collected by the first photoelectric receiving component 200 or the second photoelectric receiving component 300.

[0037] The driving circuit 100 is used to drive the laser chip to be tested to start up and emit corresponding light. Specifically, the driving circuit 100 can control the pulse width of the laser chip to be tested in cooperation with the control signal output by the external signal generator. In practical applications, when testing multiple laser chips to be tested, multiple driving circuits can be set up respectively, and each driving circuit works independently, that is, driving a single corresponding laser chip to be tested to start up and work. Furthermore, the driving circuit can include a capacitor, that is, using the rapid discharge of the capacitor to achieve short pulse driving.

[0038] The first photoelectric receiving component 200 is a component for receiving the light emitted after the laser chip to be tested is started, and then converting the optical signal into an electrical signal. It is specifically a component for collecting photoelectric signals when measuring the pulse width of the laser chip to be tested. Specifically, the receiving surface of the first photoelectric receiving component 200 can be aligned with the light-emitting surface of the laser chip to be tested to better and accurately capture the light emitted by the laser chip to be tested. The first photoelectric receiving component 200 can be a PD (Photo Diode). A photodiode is a light detector that can convert a light signal into a current or voltage signal. The working principle of a photodiode is based on the photoelectric effect. When light is irradiated on the PN junction of a photodiode, photons excite electrons in the PN junction, causing them to transition from the valence band to the conduction band, thereby generating electron-hole pairs. Under the action of the reverse voltage, these electron-hole pairs are separated and flow to the external circuit to form a photocurrent. The magnitude of the photocurrent is proportional to the intensity of the incident light, so the intensity of light can be detected by measuring the photocurrent. PD can accurately detect the pulse width of the laser chip to be tested. Therefore, when measuring the pulse width, PD can be used to receive the light emitted by the laser chip to be tested after it is started, convert it into a corresponding electrical signal, and then send the electrical signal to the host computer 400 for the next step of test analysis.

[0039] The second photoelectric receiving component 300 is also a component for receiving the light emitted after the laser chip to be tested is started, and then converting the optical signal into an electrical signal. The difference between it and the first photoelectric receiving component 200 is that it is a photoelectric receiving component for power testing requirements, which can be an integrating sphere. Specifically, the integrating sphere can be used to measure the spectrum and LIV curve (Laser-Induced Voltage) of the laser chip to be tested. Integrating sphere fluorescence spectrum testing is a method for measuring luminous flux. The basic principle is to place the light source to be tested into an integrating sphere, the inner wall of the integrating sphere is coated with a white diffuse reflection layer, and the light emitted by the light source is reflected multiple times by the sphere wall, so that the illumination on the entire sphere wall is evenly distributed. The luminous flux projected onto the photodetector through the hole in the sphere wall should be proportional to the total luminous flux emitted by the light source, thereby realizing the measurement of the spectrum. After adding a polarizer, the integrating sphere can also be used to measure the degree of polarization. Here, an integrating sphere is not used to measure the pulse width of an optical pulse less than a certain value (for example, 20 nanometers). The reason is that multiple light reflections in the integrating sphere will widen the optical pulse width. When measuring a smaller optical pulse width, there is a large deviation (generally, the measurement deviation is about 0.5 to 2 nanometers), and it is impossible to accurately measure the optical pulse width. When the optical pulse width is greater than a certain value, or when the measurement deviation is considered acceptable, an integrating sphere can also be used to measure the optical pulse width. Therefore, preferably, when measuring the optical pulse width, PD is selected as the photoelectric receiving component. In actual applications, the positions of the first photoelectric receiving component 200 and the second photoelectric receiving component 300 can be set and moved by a guide rail to facilitate the automated measurement of multiple products (laser chips to be tested).

[0040] The host computer 400 is used to select the first photoelectric receiving component 200 or the second photoelectric receiving component 300 to start according to different test parameter types to receive the light emitted by the laser chip to be tested. Specifically, if the required measurement parameter type is pulse width, the first photoelectric receiving component 200 is started to collect the light emitted by the laser chip to be tested under the drive circuit 100; if the required measurement parameter type is power, the second photoelectric receiving component 300 is started to collect the light emitted by the laser chip to be tested under the drive circuit 100. After obtaining the photoelectric signal, the host computer 400 can further calculate the parameter values ​​of the laser chip to be tested, such as pulse width and power.

[0041] The above short pulse laser test device, the entire test device includes a driving circuit 100, a first photoelectric receiving component 200, a second photoelectric receiving component 300, and a host computer 400. The laser chip to be tested emits light under the drive of the driving circuit 100, and the host computer 400 identifies the required measurement parameter type. If the required measurement parameter type is pulse width, the first photoelectric receiving component 200 is started to collect the light emitted by the laser chip to be tested under the drive of the driving circuit 100; if the required measurement parameter type is power, the second photoelectric receiving component 300 is started to collect the light emitted by the laser chip to be tested under the drive of the driving circuit 100; the host computer 400 tests the laser chip to be tested according to the photoelectric signal collected by the first photoelectric receiving component 200 or the second photoelectric receiving component 300. The entire device selects different photoelectric receiving components to collect photoelectric signals based on different test parameter types, ensuring the accuracy of the test, so it can achieve accurate short pulse laser testing.

[0042] like Figure 2 In one embodiment, the first optoelectronic receiving component 200 includes a PD 220 and an optical mode field regulating component 240 , and the optical mode field regulating component 240 is disposed on the receiving surface of the PD 220 .

[0043] For the laser chip to be tested with a small light mode, direct measurement requires optical coupling, otherwise the received power is small, which affects the measurement accuracy. For the chip with too large power, light attenuation is required to ensure accurate measurement. Therefore, in this embodiment, the first photoelectric receiving component 200 includes a light mode field adjustment component 240 in addition to PD220, and the light mode field adjustment component 240 is arranged on the receiving surface of PD220. Specifically, for the chip with a small light mode field, a first diffuser or a concave lens can be added to the receiving surface of PD220 to expand the light mode field, which can effectively be compatible with the measurement of chips with different mode field sizes, greatly reduce the coupling difficulty, and improve the test efficiency. More specifically, here, the role of the first diffuser is to diffuse the laser with a small light mode field (small light beam divergence angle). Since the receiving surface of PD220 is small, the diffused light beam is more easily received by PD220, which is conducive to the reception of signals. For the chip with a large light mode field, it is not necessary to add a diffuser or a concave lens to expand it. In addition, for the laser chip under test with too high power, the light intensity can also be attenuated by the second diffuser or light attenuation sheet. That is, for the laser chip under test with too high power, the second diffuser can be used to diffuse the light and reduce the light intensity entering the PD220.

[0044] like Figure 3 As shown, in one embodiment, the second optoelectronic receiving component 300 includes an integrating sphere 320 or a polarizing plate 340 .

[0045] Here, in addition to the integrating sphere 320, the second photoelectric receiving assembly 300 may also include a polarizing plate 340, which can be used to measure the degree of polarization. Specifically, the polarizing plate 340 is an optical element that allows a light wave vibrating in a certain direction to pass through, while preventing light waves vibrating in other directions. It works based on the polarization phenomenon of light, that is, during the propagation of light waves, the vibration direction of the light wave may have a certain regularity or orientation. In the photoelectric receiving assembly, the polarizing plate 340 is often used to selectively receive a light signal in a specific polarization state. This can be used to filter out background light, stray light or unwanted light signals, and improve the signal-to-noise ratio and accuracy of the received signal. In practical applications, the integrating sphere 320 and the polarizing plate 340 can be set at the same time, and the two work in combination. Specifically, when the integrating sphere 320 and the polarizing plate 340 work in combination, first, the integrating sphere 320 will homogenize the light received in the future, eliminate the inhomogeneity of the light, and provide a stable and uniform light signal for photoelectric reception. Then, the polarizer 340 selectively receives the optical signal of a specific polarization state as required, further purifies the received optical signal, improves the light receiving accuracy, and can also measure the polarization degree.

[0046] like Figure 4 As shown, in one embodiment, the short pulse laser testing device further includes a signal generator 500, which is connected to the driving circuit 100, and the signal generator 500 is used to output an adjustment signal to the driving circuit 100, so that the driving circuit 100 adjusts the frequency or pulse width of the laser chip to be tested.

[0047] The signal generator 500 is used to output an adjustment signal to the driving circuit 100, so as to cooperate with the driving circuit 100 to adjust the pulse width of the laser chip to be tested. Specifically, the signal generator 500 can be used to adjust the light emission period and duty cycle of the laser chip to be tested, and cooperate with the driving circuit 100 to control the pulse width of the chip. Further, the signal generator 500 can be integrated with the driving circuit 100, for example, it can be integrated in the driving board, which can greatly reduce the volume of the entire device.

[0048] like Figure 5 As shown, in one embodiment, the driving circuit 100 includes a charging module 120, a capacitor 140 and a switch tube 160 ( Figure 5 The charging module 120 is connected to the capacitor 140, the capacitor 140 is connected to the input end of the laser chip to be tested, the output end of the laser chip to be tested is connected to the input end of the switch tube 160, the output end of the switch tube 160 is grounded, and the control end of the switch tube 160 receives an external control signal.

[0049] The charging module 120 can charge the capacitor 140, and the switch tube 160 is turned on under the control of the external control signal. At this time, the capacitor 140 is discharged, and the current flows through the laser chip to be tested, and the laser chip to be tested begins to emit light. When the capacitor 140 is completely discharged or the external control signal controls the switch tube 160 to be disconnected, the current in the entire drive circuit 100 drops to 0, and the laser chip to be tested stops emitting light. In practical applications, the switch tube 160 may include a triode and a field effect tube. Preferably, GaNFET can be used here.

[0050] In practical applications, such as Figure 5 As shown, a nano-laser chip driving circuit 100 is provided here, which specifically realizes short pulse driving through the fast discharge of capacitor 140. Its entire structure consists of two parts: a discharge circuit and a fast switch, wherein the fast switch uses but does not include the use of field effect transistors, MOS transistors and other logic chips, and GaNFET is used as an example in this specific application example. The working logic of the entire driving circuit 100 is as follows:

[0051] a. After the driver board is powered (the low-voltage power supply drives each logic circuit), the charging capacitor 140 can be charged through the high-voltage power supply (which can be an external power supply or a power chip on the driver board). At this time, the voltage across the capacitor 140 quickly rises to the input voltage of the high-voltage power supply;

[0052] b. Using an external signal generator 500 or an integrated signal circuit to charge the G pole of the GaNFET, so that the GaNFET is turned on;

[0053] c. The moment the GaNFET is turned on, the charging capacitor 140 begins to discharge rapidly, and the current flows through the LD (laser chip), starting to emit light;

[0054] d. Pulse cut-off mode: 1. After the capacitor 140 is fully discharged, the circuit current gradually drops to 0; 2. By discharging the G pole of the GaNFET, the switch disconnects the loop and the current drops to 0; Mode 1 uses the discharge characteristics of the capacitor 140 to control the discharge pulse width. By changing the capacitor 140 and the inductor combination of the discharge loop, the pulse width can be changed. It is often used when the required pulse width is less than 10ns and the pulse width of the signal generator 500 does not meet the usage requirements; Mode 2 can be used to control the pulse width by signal triggering: On the one hand, the signal generator 500 can be used directly to control the GaNFET. At this time, the pulse width of the drive circuit 100 directly depends on the setting of the signal generator 500. For example, the output pulse width of the signal generator 500 is 40ns. When the driver chip is working, the optical pulse width of the chip is usually greater than 40ns. On the other hand, the signal link of the signal generator 500 can be processed by branch delay, and the signal is divided into two paths A and B. The two signals are delayed by using the RC circuit, and the delay time is t Aand t B In the RC circuit of the two signals, the resistance values ​​are R A , R B The capacitance of capacitor 140 is C A , C B , where t A ≈R A *C A , t B ≈R B *C B (Since parasitic capacitance 140, parasitic inductance and line resistance are unavoidable in the circuit, the specific values ​​need to be debugged and measured according to the actual situation). Then, the two signals are passed through an "OR" gate circuit and then input into the GaNFET. At this time, the signal width reaching the GaNFET is t s = |t A -t B |, at this time, the optical pulse width of the laser depends on the driving circuit 100 itself.

[0055] like Figure 4 As shown, in one embodiment, the short pulse laser testing device further includes an oscilloscope 600 , which is connected to the first photoelectric receiving component 200 and the host computer 400 .

[0056] The oscilloscope 600 is an electronic measuring instrument with a wide range of uses. It can transform invisible electrical signals into visible images, making it easier for people to study the changing processes of various electrical phenomena. The oscilloscope 600 uses a narrow electron beam composed of high-speed electrons to hit a screen coated with fluorescent material to produce tiny light spots. Under the action of the measured signal, the electron beam is like the tip of a pen, and can draw a curve of the change of the instantaneous value of the measured signal on the screen. The oscilloscope 600 can be used to observe the waveform curves of various signal amplitudes changing over time, and can also be used to test various electrical quantities, such as voltage, current, frequency, phase difference, amplitude modulation, etc. Here, the entire device also includes an oscilloscope 600, which is connected to the first photoelectric receiving component 200 respectively, so that the photoelectric signal collected by the first photoelectric receiving component 200 can be displayed for intuitive observation. Furthermore, when the second photoelectric receiving component 300 is an integrating sphere, a spectrometer and a power acquisition card paired with the integrating sphere can also be set, which are used to measure the spectrum and optical power respectively; wherein the spectrometer and the integrating sphere are respectively connected to the second photoelectric receiving component 300. The reason for using the acquisition card paired with the integrating sphere here is as follows: in the integrating sphere, the photocurrent is converted into optical power, usually through Power (optical power) = I (integrating sphere photocurrent) * power coefficient, where the power coefficient is different under each wavelength condition and is calibrated by the manufacturer, calibration agency, or user; the acquisition card paired with the factory usually has a calibration coefficient with the factory, and the power can be read directly. In this way, compared with directly using an oscilloscope for power measurement, the oscilloscope needs to calibrate the coefficient by itself when measuring power, and calculate the optical power data, and the testing process is cumbersome. Therefore, it is more convenient to use the acquisition card paired with the integrating sphere for optical power here.

[0057] like Figure 4 As shown, in one embodiment, the short pulse laser testing device further includes a temperature control component 700, which is connected to the host computer 400 and is used to adjust the ambient temperature of the laser chip to be tested.

[0058] The temperature control component 700 is used to set and adjust the temperature conditions so as to measure the test items at different temperatures. The temperature control adopts PID control to ensure the temperature stability. The temperature control component can be specifically a TEC (Thermo-Electric Cooler Temperature Control). TEC is a semiconductor refrigeration device based on the thermoelectric effect (including the Seebeck effect and the Peltier effect). When direct current passes through a thermocouple composed of two different semiconductor materials, one end of the thermocouple will absorb heat and cool, and the other end will release heat and heat up, thereby achieving temperature control. The TEC temperature control system achieves high-precision control of the target temperature by monitoring and controlling the operating current and voltage of the TEC device.

[0059] In practical applications, the overall structure of the short pulse laser testing device of the present application is as follows: Figure 6 As shown, the integrating sphere and PD can be set and moved by the guide rail to facilitate the automated measurement of multiple products (laser chips to be tested). Specifically, the relative position of the integrating sphere and PD can be automatically adjusted by the host computer. First, the product test has a fixed position, which is fixed by a mechanical limiter; then the mechanical guide rail uses a stepper motor, servo motor or linear motor for movement control; during each round of testing, the host computer will issue a reset operation instruction to the motor controller to determine the coordinates of the initial 0 point position; then, based on the 0 point coordinate position, the coordinates of the PD and integrating sphere test positions of each product are determined respectively; during the test, the test host computer moves the guide rail according to the coordinate position, so that the integrating sphere and PD test the products to be tested in turn according to the debugged test sequence and the coordinate position information of each product.

[0060] like Figure 7 As shown, the present application also provides a testing method for the above-mentioned short pulse laser testing device, which can be applied to the host computer of the above-mentioned short pulse laser testing device, and the method includes:

[0061] S200: responding to the start of the test operation and identifying the required test parameter type;

[0062] S400: If the required measurement parameter type is pulse width, start the first photoelectric receiving component to collect light emitted by the laser chip to be measured under the drive of the driving circuit;

[0063] S600: If the required measurement parameter type is power, start the second photoelectric receiving component to collect light emitted by the laser chip to be measured under the drive of the driving circuit;

[0064] S800: Test the laser chip to be tested according to the collected photoelectric signals.

[0065] In the test method of the short pulse laser test device, the host computer tests the laser chip to be tested according to the photoelectric signal collected by the first photoelectric receiving component or the second photoelectric receiving component. The entire scheme selects different photoelectric receiving components to collect photoelectric signals based on different test parameter types, ensuring the accuracy of the test, so it can achieve accurate short pulse laser testing.

[0066] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0067] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The above embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A short pulse laser testing device, characterized in that: The device comprises a driving circuit, a first photoelectric receiving component, a second photoelectric receiving component, and a host computer; The drive circuit is connected to the laser chip to be tested, and the host computer identifies the type of the required measurement parameter. If the required measurement parameter type is pulse width, the first photoelectric receiving component is started to collect the light emitted by the laser chip to be tested under the drive of the drive circuit; if the required measurement parameter type is power, the second photoelectric receiving component is started to collect the light emitted by the laser chip to be tested under the drive of the drive circuit; The host computer tests the laser chip to be tested according to the photoelectric signal collected by the first photoelectric receiving component or the second photoelectric receiving component.

2. The method according to claim 1, characterized in that The first photoelectric receiving component includes a PD, and the second photoelectric receiving component includes an integrating sphere.

3. The method according to claim 1, characterized in that The first photoelectric receiving component includes a PD and an optical mode field regulating component, and the optical mode field regulating component is arranged on the receiving surface of the PD.

4. The method according to claim 3, characterized in that The optical mode field adjustment component includes a first diffuser or a concave lens; or, the optical mode field adjustment component includes a second diffuser or a light attenuation plate.

5. The method according to claim 1, characterized in that The second photoelectric receiving component includes an integrating sphere or a polarizing plate.

6. The method according to claim 1, characterized in that It also includes a signal generator, which is connected to the driving circuit and is used to output an adjustment signal to the driving circuit so that the driving circuit adjusts the frequency or pulse width of the laser chip to be tested.

7. The method according to claim 1, characterized in that The driving circuit includes a charging module, a capacitor and a switch tube; The charging module is connected to the capacitor, the capacitor is connected to the input end of the laser chip to be tested, the output end of the laser chip to be tested is connected to the input end of the switch tube, the output end of the switch tube is grounded, and the control end of the switch tube receives an external control signal.

8. The method according to claim 1, characterized in that: It also includes an oscilloscope, which is connected to the first photoelectric receiving component.

9. The method according to claim 1, characterized in that: It also includes a temperature control component, which is connected to the host computer and is used to adjust the ambient temperature of the laser chip to be tested.

10. A method for testing a short pulse laser testing device according to any one of claims 1 to 9, characterized in that: The method comprises: In response to initiating a test operation, identifying a desired test parameter type; If the required measurement parameter type is pulse width, the first photoelectric receiving component is started to collect the light emitted by the laser chip to be measured under the drive of the drive circuit; If the required measurement parameter type is power, the second photoelectric receiving component is started to collect the light emitted by the laser chip to be measured under the drive of the drive circuit; The laser chip to be tested is tested according to the collected photoelectric signals.

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