CN207625073U - A kind of scanning semiconductor laser device based on MEMS - Google Patents

Abstract

The utility model provides a MEMS-based scanning semiconductor laser, comprising: a packaging base, a semiconductor laser chip, a collimating lens and a MEMS oscillating mirror; It is packaged together with the MEMS vibrating mirror, and the relative position between the three is fixed; the semiconductor laser chip is used to emit the laser beam; the collimator lens is used to collimate the laser beam; the MEMS The vibrating mirror is used to reflect the laser beam to deflect the outgoing direction of the laser beam; the MEMS vibrating mirror reciprocates in two-dimensional space under the drive of the driving signal, so that the laser beam reflected by the MEMS vibrating mirror The beam becomes a scanning laser beam. The utility model greatly reduces the size of the laser light source, reduces the pressure for subsequent laser scanning and shaping, and is more conducive to the miniaturization of the laser sensor.

Description

A scanning semiconductor laser based on MEMS

technical field

The utility model relates to the technical field of semiconductor lasers, in particular to a MEMS-based scanning semiconductor laser.

Background technique

With the maturity of technology, the application of semiconductor lasers is becoming more and more extensive. Due to the characteristics of small size and low cost of semiconductor lasers, there is a huge market for their application in commercial laser sensors.

However, semiconductor lasers often need to cooperate with larger scanning components, such as rotating mirrors, to realize beam scanning during use.

In order to further reduce the size of the laser sensor, a miniaturized and integrated semiconductor laser light source is required.

Utility model content

Aiming at the defects in the prior art, the utility model provides a scanning semiconductor laser based on MEMS. The utility model greatly reduces the size of the laser light source, reduces the pressure for subsequent laser scanning and shaping, and is more conducive to the laser sensor. miniaturization.

In order to achieve the above object, the utility model provides the following technical solutions:

A MEMS-based scanning semiconductor laser, comprising: a packaging substrate, a semiconductor laser chip, a collimating lens, and a MEMS vibrating mirror;

The packaging substrate is used to package the semiconductor laser chip, the collimating lens and the MEMS vibrating mirror together, and fix the relative positions among the three;

The semiconductor laser chip is used to emit laser beams;

The collimating lens is used to collimate the laser beam;

The MEMS vibrating mirror is used to reflect the laser beam so that the outgoing direction of the laser beam is deflected;

Wherein, the MEMS oscillating mirror reciprocates in two-dimensional space under the driving signal, so that the laser beam reflected by the MEMS oscillating mirror becomes a scanning laser beam.

Preferably, the collimating lens is located between the semiconductor laser chip and the MEMS vibrating mirror, and the laser beam emitted by the semiconductor laser chip is collimated by the collimating lens and collimated by the MEMS vibrating mirror. The straight laser beam is deflected.

Preferably, the MEMS oscillating mirror is located between the semiconductor laser chip and the collimating lens, and the laser beam emitted by the semiconductor laser chip is deflected by the MEMS galvanizing mirror before being deflected by the collimating lens. collimation.

Preferably, the MEMS oscillating mirror vibrates around the first-dimensional vibration axis in the first-dimensional vibration plane and around the second-dimensional vibration axis in the second-dimensional vibration plane under the drive of the driving signal; wherein, the first dimension The vibration axis is on the same plane as the light-emitting section of the semiconductor laser chip, and the second-dimensional vibration axis is perpendicular to the light-emitting section of the semiconductor laser chip.

Preferably, the semiconductor laser chip coincides with the optical axis of the collimating lens, the optical axis of the collimating lens is located at the mirror center of the MEMS vibrating mirror, and the mirror normal of the initial position of the MEMS vibrating mirror is the same as the The optical axis of the collimating lens forms an included angle of 45 degrees.

Preferably, the packaging substrate includes: a semiconductor laser chip base, a MEMS vibrating mirror chip base, a collimator lens base, and a packaging base;

The semiconductor laser chip base is used to package the semiconductor laser chip and fix its position;

The MEMS vibrating mirror chip base is used to package the MEMS vibrating mirror and fix its position;

The collimating lens base is used to fix the collimating lens;

The package base is used to support and fix the base of the semiconductor laser chip, the base of the MEMS vibrating mirror chip and the base of the collimating lens.

Preferably, a notch is provided at the front end of the base of the semiconductor laser chip, so as to prevent the divergent beam emitted from the semiconductor laser chip from being blocked.

Preferably, the upper surface of the semiconductor laser chip base is plated with a layer of gold as an electrode, and a thin notch divides the semiconductor laser chip base into two parts, the left side and the right side, the left side is the positive pole, and the right side is the negative pole ;

Correspondingly, the lower side of the semiconductor laser chip is the anode, which is directly attached to the left side of the base of the semiconductor laser chip, so as to ensure that the optical axis of the outgoing beam coincides with the optical axis of the collimating lens, and the semiconductor laser chip The negative pole of the semiconductor laser chip is connected to the negative pole of the base of the semiconductor laser chip by punching a gold wire.

Preferably, the semiconductor laser further includes: an external controller configured to output a driving signal for controlling the vibration of the MEMS vibrating mirror.

It can be seen from the above technical solution that the MEMS-based scanning semiconductor laser provided by the utility model packages the semiconductor laser chip, the collimating lens and the MEMS vibrating mirror together, and realizes the collimation of the light beam of the semiconductor laser and the alignment of the laser beam. Scanning greatly reduces the size of the light source used by the laser sensor, reduces the pressure for subsequent laser scanning and shaping, and is more conducive to the miniaturization of the laser sensor.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present utility model. Those skilled in the art can also obtain other drawings based on these drawings without any creative work.

Fig. 1 is the structural representation of the scanning type semiconductor laser based on MEMS that the utility model embodiment provides;

Fig. 2 is a structural schematic diagram of a packaging substrate;

3 is a schematic diagram of the working principle of the MEMS-based scanning semiconductor laser provided by the embodiment of the present invention;

Among them, the meanings of the labels in the above figures are as follows:

100 represents the semiconductor laser chip; 101 represents the static outgoing light; 102 represents the scanning outgoing light; 200 represents the MEMS vibrating mirror; 300 represents the collimating lens; 301 represents the optical axis of the collimating lens; 400 represents the packaging substrate; 401 represents the base of the semiconductor laser chip; 402 represents the base of the MEMS vibrating mirror chip; 403 represents the base of the collimating lens; 404 represents the negative of the package; 405 represents the positive electrode of the laser drive; 406 represents the negative electrode of the laser drive; 407 represents the GN pole 1; 408 represents the GN pole 2; X-direction drive pole; 410 represents the Y-direction drive pole of the MEMS vibrating mirror; 501 represents the first-dimensional vibration axis; 502 represents the second-dimensional vibration axis; 503 represents the T ₀ beam; 504 represents the T ₁ beam; 505 represents the T ₁ beam in The deflection component in the X direction; 506 represents the deflection component of the T ₁ beam in the Y direction.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described The embodiments are some embodiments of the present utility model, but not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of the present utility model.

The embodiment of the utility model provides a MEMS-based scanning semiconductor laser, referring to FIG. 1 , the semiconductor laser includes: a packaging substrate 400, a semiconductor laser chip 100, a MEMS oscillating mirror 200 and a collimating lens 300;

The packaging substrate 400 is used to package the semiconductor laser chip 100, the MEMS vibrating mirror 200 and the collimating lens 300 together, and fix the relative positions of the three;

The semiconductor laser chip 100 is used to emit a laser beam;

The MEMS vibrating mirror 200 is used to reflect the laser beam so that the outgoing direction of the laser beam is deflected;

The collimating lens 300 is used to collimate the laser beam;

Wherein, the MEMS vibrating mirror 200 vibrates back and forth in a two-dimensional space under the driving signal, so that the laser beam reflected by the MEMS vibrating mirror 200 becomes a scanning laser beam.

1, the collimator lens 300 is located between the semiconductor laser chip 100 and the MEMS vibrating mirror 200, and the semiconductor laser chip (that is, the semiconductor laser tube core) 100 emits a divergent laser beam, and the divergent The laser beam is collimated after passing through the collimating lens 300. The MEMS vibrating mirror 200 is located in front of the collimating lens. The MEMS vibrating mirror 200 can vibrate in the two-dimensional direction, and the two directions are perpendicular to each other, so that the laser beam can move in the two-dimensional direction. on the deflection. In the initial state, the angle between the mirror surface of the MEMS galvanometer and the optical axis 301 of the collimating lens is 45 degrees, and the collimated laser beam passes through the MEMS galvanometer 200, and the optical path is deflected by 90 degrees, and finally emerges. The MEMS oscillating mirror 200 vibrates back and forth in a two-dimensional space after being driven, and the collimated laser beam 101 becomes a scanning laser beam 102 .

In this embodiment, the collimating lens 300 is located between the semiconductor laser chip 100 and the MEMS vibrating mirror 200, in other embodiments, the collimating lens 300 may also be located behind the MEMS vibrating mirror 200, That is to say, the semiconductor laser chip 100 emits a laser beam. After passing through the MEMS vibrating mirror 200 , the laser beam is deflected from the optical path, and then passes through the collimating lens 300 to collimate and exit.

FIG. 2 is a schematic structural diagram of the packaging substrate provided in this embodiment. The packaging substrate 400 mainly includes the following parts: a semiconductor laser chip base 401 , a MEMS oscillating mirror chip base 402 , a collimator lens base 403 and a package base 404 .

The semiconductor laser chip base 401 is used to package the semiconductor laser chip 100 . Preferably, a gap is provided at the front end of the semiconductor laser chip base 401 to prevent the divergent light beam emitted from the semiconductor laser chip 100 from being blocked. In addition, the upper surface of the semiconductor laser chip base 401 is plated with gold as an electrode, and the semiconductor laser chip base 401 is divided into two parts by a thin notch, the left side is the positive pole, and the right side is the negative pole. The lower side of the semiconductor laser chip 100 is positive, which is directly attached to the left side of the semiconductor laser chip base 401, so as to ensure that the optical axis of the outgoing light beam coincides with the optical axis 301 of the collimating lens, and the semiconductor laser chip 100 The negative electrode of the semiconductor laser chip base 401 is connected to the negative electrode of the semiconductor laser chip base 401 by way of gold wire.

The collimating lens base 403 is used to fix the collimating lens 300, and the MEMS vibrating mirror chip base 402 is used to package the MEMS vibrating mirror 200, fix its position, and provide power for its operation. The package base 404 is used to fix the semiconductor laser chip 100 , the MEMS vibrating mirror 200 and the collimating lens 300 .

When the packaging substrate 400 is set, it is necessary to ensure that the optical axes of the semiconductor laser chip 100 and the collimator lens 300 coincide, and the optical axis 301 of the collimator lens is located at the mirror center of the MEMS oscillating mirror 200, and at the same time It is ensured that the mirror surface normal of the MEMS vibrating mirror and the optical axis 301 of the collimating lens form an included angle of 45 degrees.

Preferably, referring to FIG. 2 , six electrode pins are provided at the bottom of the packaging substrate 400, which are laser-driven positive pole 405, laser-driven negative pole 406 (not shown in the figure), GN pole 1407, and GN pole 2 408 ( not shown in the figure), the X-direction driving pole 409 of the MEMS vibrating mirror, and the Y-direction driving pole 410 of the MEMS vibrating mirror (not shown in the figure). The laser driving anode 405 and the laser driving cathode 406 are used to provide a high voltage signal for the semiconductor laser chip 100 to make the semiconductor laser chip 100 emit light. The X-direction driving pole 409 of the MEMS vibrating mirror is used to provide a driving signal for the MEMS vibrating mirror 200 to vibrate in the X-axis direction, and the Y-direction driving pole 410 of the MEMS vibrating mirror is used to provide a driving signal for the MEMS vibrating mirror. 200 vibrates in the X-axis direction to provide a driving signal.

FIG. 3 is a schematic diagram of the working principle of the MEMS-based scanning semiconductor laser provided in this embodiment. Referring to FIG. 3 , the MEMS oscillating mirror 200 vibrates in the first-dimensional vibration plane around the first-dimensional vibration axis 501 and vibrates in the second-dimensional vibration plane around the second-dimensional vibration axis 502 under the drive of the driving signal; wherein, the The first-dimensional vibration axis 501 is on the same plane as the light-emitting section of the semiconductor laser chip 100 , and the second-dimensional vibration axis 502 is perpendicular to the light-emitting section of the semiconductor laser chip 100 .

The external controller supplies power to the semiconductor laser through the above-mentioned electrodes 405-410. The laser-driven positive electrode 405 and the laser-driven negative electrode 406 drive the semiconductor laser chip 100 to emit a beam of light after receiving a high-voltage pulse signal. When the beam divergence angle is relatively large, the energy is relatively scattered, and the divergence angle of the laser beam becomes smaller after passing through the collimating lens 300 . The compressed laser beam is incident on the MEMS oscillating mirror 200, and while the laser is emitting light, the X-direction driving pole 409 of the MEMS oscillating mirror and the Y-direction driving pole 410 of the MEMS oscillating mirror also receive a driving signal, Vibration occurs in the X-axis direction and the Y-axis direction. Wherein, the X-axis direction and the Y-axis direction are perpendicular to each other.

It can be understood that the driving signal of the X-direction driving pole 409 of the MEMS oscillating mirror, the Y-direction driving pole 410 of the MEMS oscillating mirror and the driving signal of the semiconductor laser chip 100 jointly determine the scanning mode and scanning point of the outgoing beam. density.

Referring to Fig. 3, at T ₀ moment, described semiconductor laser chip sends out a bunch of laser pulses, and this moment, described MEMS vibrating mirror deflection angle is θ ₀ , and laser pulse emission direction is T ₀ beam 503, at T ₁ moment, described The semiconductor laser chip sends out a beam of laser pulse _T1 light beam 504. Compared with _T0 time, the MEMS vibrating mirror 200 deflects at an angle of α in the X direction, and the MEMS vibrating mirror 200 deflects at an angle of β in the Y direction. The pulse emission direction is the T ₁ beam 504, the deflection component of the T ₁ beam in the X direction is equal to 2α; the deflection component of the T ₁ beam in the Y direction is equal to 2β. In FIG. 3 , 505 represents the deflection component of the T ₁ beam in the X direction, and 506 represents the deflection component of the T ₁ beam in the Y direction.

As can be seen from the above description, the MEMS-based scanning semiconductor laser provided in this embodiment packages the semiconductor laser chip, collimating lens and MEMS vibrating mirror together to realize the collimation of the light beam of the semiconductor laser and the scanning of the laser beam , which greatly reduces the size of the light source used by the laser sensor, reduces the pressure for subsequent laser scanning and shaping, and is more conducive to the miniaturization of the laser sensor.

The above embodiments are only used to illustrate the technical solutions of the present utility model, and are not intended to limit it; although the utility model has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be applied to the foregoing implementations. The technical solutions described in the examples are modified, or some of the technical features are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (9)

1. A scanning semiconductor laser based on MEMS, is characterized in that, comprises: packaging substrate, semiconductor laser chip, collimating lens and MEMS vibrating mirror; The packaging substrate is used to package the semiconductor laser chip, the collimating lens and the MEMS vibrating mirror together, and fix the relative positions among the three; The semiconductor laser chip is used to emit laser beams; The collimating lens is used to collimate the laser beam; The MEMS vibrating mirror is used to reflect the laser beam so that the outgoing direction of the laser beam is deflected; Wherein, the MEMS oscillating mirror reciprocates in two-dimensional space under the driving signal, so that the laser beam reflected by the MEMS oscillating mirror becomes a scanning laser beam. 2. semiconductor laser according to claim 1, is characterized in that, described collimating lens is positioned between described semiconductor laser chip and described MEMS vibrating mirror, and the laser light beam that described semiconductor laser chip emits passes through described collimation. After the lens is collimated, the collimated laser beam is deflected by the MEMS vibrating mirror. 3. The semiconductor laser according to claim 1, wherein the MEMS oscillating mirror is located between the semiconductor laser chip and the collimating lens, and the laser beam emitted by the semiconductor laser chip passes through the MEMS oscillating lens. After the direction deflection by the mirror, the collimation lens is used for collimation. 4. The semiconductor laser according to claim 1, wherein the MEMS oscillating mirror vibrates around the first-dimensional vibration axis in the first-dimensional vibration plane and around the second-dimensional vibration axis in the second dimension under the drive of the driving signal. Vibration in a three-dimensional vibration plane; wherein, the first-dimensional vibration axis is on the same plane as the light-emitting section of the semiconductor laser chip, and the second-dimensional vibration axis is perpendicular to the light-emitting section of the semiconductor laser chip. 5. semiconductor laser device according to claim 1, is characterized in that, the optical axis of described semiconductor laser chip and described collimating lens coincides, and the optical axis of described collimating lens is positioned at the mirror surface center of described MEMS vibrating mirror, The mirror surface normal of the initial position of the MEMS vibrating mirror and the optical axis of the collimating lens form an included angle of 45 degrees. 6. semiconductor laser device according to claim 1, is characterized in that, described packaging base comprises: semiconductor laser chip base, MEMS oscillating mirror chip base, collimating lens base and packaging base; The semiconductor laser chip base is used to package the semiconductor laser chip and fix its position; The MEMS vibrating mirror chip base is used to package the MEMS vibrating mirror and fix its position; The collimating lens base is used to fix the collimating lens; The package base is used to support and fix the base of the semiconductor laser chip, the base of the MEMS vibrating mirror chip and the base of the collimating lens. 7 . The semiconductor laser according to claim 6 , wherein a gap is provided at the front end of the base of the semiconductor laser chip to prevent the divergent light beam emitted from the semiconductor laser chip from being blocked. 8. The semiconductor laser according to claim 6, wherein the upper surface of the semiconductor laser chip base is plated with a layer of gold as an electrode, and the semiconductor laser chip base is divided into left and right sides by a thin notch. There are two parts on the side, the left side is the positive pole, and the right side is the negative pole; Correspondingly, the lower side of the semiconductor laser chip is the anode, which is directly attached to the left side of the base of the semiconductor laser chip, so as to ensure that the optical axis of the outgoing beam coincides with the optical axis of the collimating lens, and the semiconductor laser chip The negative pole of the semiconductor laser chip is connected to the negative pole of the base of the semiconductor laser chip by punching a gold wire. 9. The semiconductor laser according to claim 1, further comprising: an external controller, the external controller is used for outputting a driving signal for controlling the vibration of the MEMS vibrating mirror.