CN110749782A

CN110749782A - Pulse drive test method for semiconductor laser

Info

Publication number: CN110749782A
Application number: CN201810809210.3A
Authority: CN
Inventors: 刘洪武; 汤庆敏; 刘存志; 周莉
Original assignee: Weifang Huaguang Photoelectron Co Ltd
Current assignee: Weifang Huaguang Photoelectron Co Ltd
Priority date: 2018-07-23
Filing date: 2018-07-23
Publication date: 2020-02-04
Anticipated expiration: 2038-07-23
Also published as: CN110749782B

Abstract

A pulse drive test method for a semiconductor laser comprises the following steps: the pulse peak test is carried out in the T1 time period, and the large current impact resistance of the laser is mainly tested. The T2 time period is a high-frequency test, mainly tests the reliability performance of the laser at high frequency, the T3 time period test is an LD reliability analysis, and is used for long-term evaluation or adjustment according to data fed back by customers after testing the laser tube performance at the T1 stage and the T2 stage. Through the three-stage test, a complete and reliable test can be realized for various performances of the laser, and the accuracy and comprehensiveness of the laser test are improved.

Description

Pulse drive test method for semiconductor laser

Technical Field

The invention relates to the technical field of semiconductor testing, in particular to a pulse driving testing method for a semiconductor laser.

Background

The aging test of the semiconductor laser is to screen out products with poor reliability through the test before delivery. The prior aging test generally uses a direct current test, or a constant power test. With the changing market demand, the light emission intensity during the LD is increased in order to reduce the operating time of the LD. More and more manufacturers adopt pulse current driving as LD working driving current. The pulse-driven test method is designed to comply with market changes, test the reliability of the produced LD under the pulse, and explore the critical point of LD failure under the pulse driving. Whether the pulse driving is performed or not can not be distinguished by naked eyes under the high-frequency pulse driving, but the instantaneous brightness of the pulse driving is higher under the same effective current, so that the pulse driving method is widely applied to the market of a reticle instrument and the like.

The assembly of the LD pulse burn-in test apparatus is limited by the pulse power supply. For the convenience of testing and monitoring the current, a series test is generally adopted, and a pulse signal as shown in figure 1 is output by a unipolar power supply and loaded on all the tubes. However, the frequency of the pulse signal and the intensity of the current signal emitted by the laser are regular rectangular waves, which cannot meet the test of various indexes of the laser.

Disclosure of Invention

In order to overcome the defects of the technology, the invention provides a pulse driving test method of a semiconductor laser, which is used for carrying out pulse peak value test, high frequency test and constant peak current and constant frequency test on the laser.

The technical scheme adopted by the invention for overcoming the technical problems is as follows:

a pulse drive test method for a semiconductor laser comprises the following steps:

a) in a T1 time period, the semiconductor laser aging tester outputs N pulse signals with equal frequency from 0 moment to the laser, and the output time of each pulse signal is X_nPeak current intensity Y of each pulse signal₁To Y_nAccording to formula Y_n＝k₁＜X_nFunction change calculated by >. A, where k₁Is a slope when X_n-[X_n]When > D, A is 0, when X is_n-[X_n]When D is less than A is 1, D is duty ratio, and its value is 0.1-0.99, [ X_n]Is a rounding function, whose value is not greater than X_nMaximum integer of, < X_nIs a ceiling function;

b) in a time period T2 after a time period T1, the semiconductor laser aging tester outputs M pulse signals with equal peak current intensity to the laser at the same peak current, and the frequency F (X) of the pulse signal of each pulse signal₁) To F(X_n) According to the formula F (X)_n)＝k₂＜X_mFunction change calculated by >. A, where k₂Is a slope, X_mFor the time when the output of each pulse signal is in the period T2, < X_mIs a ceiling function;

c) the semiconductor laser aging tester outputs P pulse signals at the same peak current and the same frequency during a T3 period after the T2 period.

Preferably, k in step a)₁K is not less than 1₁Less than or equal to 3, and the unit is Hz/s.

Preferably, X in step a)_n≤3×P_{Rated value}，P_{Rated value}Is the rated power of the semiconductor laser.

Preferably, 1. ltoreq. k in step b)₂≤3，k₂The unit is Hz/s.

Preferably, F (X) in step b)_n) Less than or equal to the failure critical point of the laser under the high-frequency pulse current.

Preferably, the peak current in step c) is equal to or less than the maximum peak current intensity in step a), and the frequency in step c) is equal to or less than the maximum pulse signal frequency in step b).

The invention has the beneficial effects that: the pulse peak test is carried out in the T1 time period, and the large current impact resistance of the laser is mainly tested. The T2 time period is a high-frequency test, mainly tests the reliability performance of the laser at high frequency, the T3 time period test is an LD reliability analysis, and is used for long-term evaluation or adjustment according to data fed back by customers after testing the laser tube performance at the T1 stage and the T2 stage. Through the three-stage test, a complete and reliable test can be realized for various performances of the laser, and the accuracy and comprehensiveness of the laser test are improved.

Drawings

FIG. 1 is a diagram of pulse signals during a conventional semiconductor laser test;

FIG. 2 is a test waveform of the present invention.

Detailed Description

The invention will be further explained with reference to fig. 1 and 2.

a) in a T1 time period, the semiconductor laser aging tester outputs N pulse signals with equal frequency from 0 moment to the laser, and the output time of each pulse signal is X_nPeak current intensity Y of each pulse signal₁To Y_nAccording to formula Y_n＝k₁＜X_nFunction change calculated by >. A, where k₁Is a slope when X_n-[X_n]When > D, A is 0, when X is_n-[X_n]When D is less than A is 1, D is duty ratio, and its value is 0.1-0.99, [ X_n]Is a rounding function, whose value is not greater than X_nMaximum integer of, < X_n> is an ceiling function. The pulse peak test is carried out in the T1 time period, and the large current impact resistance of the laser is mainly tested. By continuously outputting N pulse signals with equal frequency, the test can be carried out until the laser fails. The peak current intensity is gradually improved by setting function change, and the pulse peak current at the failure critical point can be accurately measured.

b) In a time period T2 after a time period T1, the semiconductor laser aging tester outputs M pulse signals with equal peak current intensity to the laser at the same peak current, and the frequency F (X) of the pulse signal of each pulse signal₁) To F (X)_n) According to the formula F (X)_n)＝k₂＜X_mFunction change calculated by >. A, where k₂Is a slope, X_mFor the time when the output of each pulse signal is in the period T2, < X_m> is an ceiling function. The time period of T2 is high frequency test, mainly testing the reliability of the laser under high frequency, the current peak value is equal during the test, and the pulse frequency is adjusted according to a certain function change.

c) The semiconductor laser aging tester outputs P pulse signals at the same peak current and the same frequency during a T3 period after the T2 period. The T3 time period test is for LD reliability analysis, and is used for long-term evaluation or adjustment according to data fed back by the customer after testing the laser tube performance in the T1 stage and the T2 stage. Through the three-stage test, a complete and reliable test can be realized for various performances of the laser, and the accuracy and comprehensiveness of the laser test are improved.

Example 1:

in step a) k₁K is not less than 1₁Less than or equal to 3, and the unit is Hz/s.

Example 2:

x in step a)_n≤3×P_{Rated value}，P_{Rated value}Is the rated power of the semiconductor laser.

Example 3:

k is not less than 1 in the step b)₂≤3，k₂The unit is Hz/s.

Example 4:

f (X) in step b)_n) Less than or equal to the failure critical point of the laser under the high-frequency pulse current.

Example 5:

the peak current in the step c) is less than or equal to the maximum peak current intensity in the step a), and the frequency in the step c) is less than or equal to the maximum pulse signal frequency in the step b).

Claims

1. A pulse drive test method for a semiconductor laser is characterized by comprising the following steps:

a) outputting N pulse signals with equal frequency to the laser from 0 moment by the semiconductor laser aging tester in a T1 time period, wherein the time of outputting each pulse signal in the T1 time period is X_nPeak current intensity Y of each pulse signal₁To Y_nAccording to formula Y_n＝k₁＜X_nFunction change calculated by >. A, where k₁Is a slope when X_n-[X_n]When > D, A is 0, when X is_n-[X_n]When D is less than A is 1, D is duty ratio, and its value is 0.1-0.99, [ X_n]Is a rounding function, whose value is not greater than X_nMaximum integer of, < X_nIs a ceiling function;

b) semiconductor laser in T2 period after T1 periodThe aging tester outputs M pulse signals with equal peak current intensity to the laser at the same peak current, and the frequency F (X) of the pulse signal of each pulse signal₁) To F (X)_n) According to the formula F (X)_n)＝k₂＜X_mFunction change calculated by >. A, where k₂Is a slope, X_mFor the time when the output of each pulse signal is in the period T2, < X_mIs a ceiling function;

2. The pulsed drive test method for a semiconductor laser according to claim 1, characterized in that: in step a) k₁K is not less than 1₁Less than or equal to 3, and the unit is Hz/s.

3. The pulsed drive test method for a semiconductor laser according to claim 1, characterized in that: x in step a)_n≤3×P_{Rated value}，P_{Rated value}Is the rated power of the semiconductor laser.

4. The pulsed drive test method for a semiconductor laser according to claim 1, characterized in that: k is not less than 1 in the step b)₂≤3，k₂The unit is Hz/s.

5. The pulsed drive test method for a semiconductor laser according to claim 1, characterized in that: f (X) in step b)_n) Less than or equal to the failure critical point of the laser under the high-frequency pulse current.

6. The pulsed drive test method for a semiconductor laser according to claim 1, characterized in that: the peak current in the step c) is less than or equal to the maximum peak current intensity in the step a), and the frequency in the step c) is less than or equal to the maximum pulse signal frequency in the step b).