CN208027073U - Miniature two-dimensional laser scanning image source and projection system - Google Patents

Abstract

The utility model discloses a miniature two-dimensional laser scanning image source and a projection system. The miniature two-dimensional laser scanning image source includes: a laser light source, a lens unit, a scanning vibrating mirror unit, a display unit and a control unit, the lens unit and the scanning vibrating mirror unit are sequentially arranged between the laser light source and the display unit, and the The laser light source is at least used to emit the laser beam; the lens unit is at least used to form the laser beam emitted by the laser light source into a converging beam; the scanning galvanometer unit is at least used to reflect the converging beam and enter the display unit; the display The unit is at least used to receive the condensed beam reflected by the scanning galvanometer unit; the control unit is respectively connected with the laser light source and the scanning galvanometer unit. The utility model utilizes a two-dimensional scanning galvanometer and a laser to produce a small-volume, high-resolution, high-brightness, high-contrast image source, and applies the two-dimensional scanning laser image source to fields such as HUD, VR, and AR.

Description

Miniature two-dimensional laser scanning image source and projection system

technical field

The utility model particularly relates to a miniature two-dimensional laser scanning image source and a projection system, belonging to the technical field of micro-nano manufacturing.

Background technique

Images are the most commonly used information carriers in human social activities, and image sources refer to modules that can generate images. With the development of technology, image source applications are becoming more and more extensive. In the field of car driving, in order to drive more safely and conveniently, some speed image information needs to be displayed in front of the driver (such as the windshield). This system is called HUD (headup display); in VR (virtual reality), AR (augmented Reality) and other fields, it is necessary to wear a HMD (head mounted display) to present various image information in front of the human eyes; both these HUDs and HMDs have image sources. Different applications have different requirements for the image source. In VR and AR applications, people need to wear it. It is hoped that the image source is small in size, light in weight, high in resolution, and low in power consumption. HUD needs to consider the stability and shock resistance of the system. , high temperature resistance, and can still display image information well under bright and dark ambient light conditions.

Common image sources currently on the market include: DLP image sources, OLED image sources, LCD image sources, etc.; these image sources were originally applied to TVs and projectors. After redesigning and reducing the size of the original system, they can be easily applied to HUD, HMD.

DLP (Digital Light Processing) image source technology is the projection technology of Ti Company in the United States, the core part of which is the image chip DMD, which is an array of a large number of tiny mirrors, and each micro mirror corresponds to a pixel of the image. The whole system mainly includes a light source system, a DMD chip, and a projection lens. The light source system commonly uses LEDs, xenon lamps and other light sources, and uses some optical devices to homogenize the light emitted by the light source and incident it on the DMD chip; by controlling the micromirrors in the DMD chip The grayscale information of the image can be obtained by deflection. When the RGB three-color grayscale patterns are superimposed, a color image can be seen; the projection lens is composed of a series of optical lenses, and its function is to image the DMD chip on the screen. Figure 1 shows Projection system with LED as light source.

The LCD (Liquid Crystal Display) image source is a miniaturized LCD TV, which can be simply divided into two parts: the LCD panel and the backlight module. The liquid crystal panel part mainly includes: polarizer, color filter, liquid crystal molecules, TFT circuit, polarizer, and the backlight module includes a diffusion film, a brightness enhancement film, a light guide plate and a backlight, and the commonly used backlight is LED; When a voltage is applied, the liquid crystal molecules will turn due to twisting and then change the optical rotation state, which is similar to the image grayscale information displayed by many small light valves. The light emitted by the backlight passes through the first polarizer and enters the liquid crystal layer, and then passes through color filters and a second layer of polarizer so that the image can be seen on the screen.

OLED (Organic Light Emitting Diodes, Organic Light Emitting Diodes) image source can be simply divided into three parts: TFT substrate, organic light-emitting material and polarizer. The substrate is generally made of transparent glass, and there will be a layer of anode material on the surface of the glass to apply voltage to the organic material. ; When a voltage is applied to the organic material, the electrons of the organic molecule transition, and the electrons release light quanta during the transition from the excited state to the ground state, thereby generating visible light. There are RGB three light-emitting organic materials in each pixel, and the color pattern output is realized by controlling the applied voltage. For details of the above existing technologies, please refer to "Research on Small and Medium Size OLED Display and Module Driving Technology, Han Pengfei", "Research and Realization of Power Consumption Reduction Method for TFT-LCD and OLED Image Display, Zhuang Yanjian", "Enabling the Next Generation of Automotive Head-UP DisplaySystems, Texas Instruments, DLPA043-October 2013".

However, there are many components in the DLP image source system, the system is relatively complex, and its light efficiency is low, the power consumption is large, and the volume is large, so it is difficult to apply it to the head-mounted display, especially in the dark environment, there will be weak light The area affects the visual effect, especially when driving at night, which has certain safety hazards; LCD requires LED backlight, and the image information cannot achieve high contrast. Dark pixels in the LCD are produced by blocking the backlight, but the light cannot be completely blocked, and when in a low ambient light background (such as at night), the result is that the projected image appears transparent in addition to the necessary information such as speed Rectangular bright area (full image size), these glowing rectangles can distract the driver and affect the observation of road information. In addition, the lifespan of LCD is relatively short; OLED image source is a new type of display technology, and the price is high; the color purity of blue light and red light emitted by OLED is not enough, and it is difficult to restore the most authentic image information. The lifespan of OLED is relatively short. As the usage time increases, the aging rate of different organic materials is different, which will lead to discoloration of the image. The light source shown above is a wide-spectrum light source, and a certain color filter is required to obtain a narrow-spectrum light source, and the efficiency is relatively low.

Utility model content

Aiming at the deficiencies of the prior art, the main purpose of this utility model is to provide a miniature two-dimensional laser scanning image source and projection system to overcome the deficiencies of the prior art.

For realizing aforementioned utility model object, the technical scheme that the utility model adopts comprises:

The embodiment of the utility model provides a miniature two-dimensional laser scanning image source, including: a laser light source, a lens unit, a scanning vibrating mirror unit, a display unit and a control unit, and the lens unit and the scanning vibrating mirror unit are sequentially arranged on the Between the laser light source and the display unit, the laser light source is at least used to emit a laser beam; the lens unit is at least used to form the laser beam emitted by the laser light source into a converged beam; the scanning galvanometer unit is at least used to reflect the converged The light beam is incident on the display unit; the display unit is at least used to receive the converging light beam reflected by the scanning galvanometer unit; the control unit is connected to the laser light source and the scanning galvanometer unit respectively, and the control unit is at least used to control the laser light source and the scanning galvanometer unit. The operating status of the scanner unit.

The embodiment of the utility model also provides a projection system, including the miniature two-dimensional laser scanning image source.

The embodiment of the present invention also provides the application of the miniature two-dimensional laser scanning image source or the projection system in the fields of HUD, HMD, VR and AR.

Compared with the prior art, the utility model provides a miniature two-dimensional laser scanning image source with fewer elements and high light utilization efficiency; the laser used has low power and low power consumption; no additional heat dissipation system is required, the system structure is simple and the volume is small , Portable; the two-dimensional scanning galvanometer is in a resonant state, and the power consumption is low; the laser light source can achieve high contrast and high brightness, so that the image can be well observed in a bright environment, and the two-dimensional scanning MEMS micromirror is used for imaging. The scanning laser light source can only display the necessary pixel information, avoiding a small amount of weak light in other areas, can achieve high contrast of image source images, and improve the recognition and clarity of AR, VR, and HUD display information and images.

Description of drawings

1 is a schematic diagram of the principle of a projection system using LED as a light source in a DLP image source in the prior art;

Fig. 2 is a schematic diagram of the structure and principle of a miniature two-dimensional laser scanning image source in a typical implementation case of the present invention.

Detailed ways

In view of the deficiencies in the prior art, the inventor of this case has been able to propose the technical solution of the utility model through long-term research and extensive practice. The technical solution, its implementation process and principle will be further explained as follows.

The embodiment of the utility model provides a miniature two-dimensional laser scanning image source, including: a laser light source, a lens unit, a scanning vibrating mirror unit, a display unit and a control unit, and the lens unit and the scanning vibrating mirror unit are sequentially arranged on the Between the laser light source and the display unit, the laser light source is at least used to emit a laser beam; the lens unit is at least used to form the laser beam emitted by the laser light source into a converged beam; the scanning galvanometer unit is at least used to reflect the converged The light beam is incident on the display unit; the display unit is at least used to receive the converging light beam reflected by the scanning galvanometer unit; the control unit is connected to the laser light source and the scanning galvanometer unit respectively, and the control unit is at least used to control the laser light source and the scanning galvanometer unit. The operating status of the scanner unit.

Preferably, the laser light source includes any one of semiconductor lasers and fiber lasers for emitting RGB three colors, but is not limited thereto.

Further, the scanning galvanometer unit is selected from reflective mirrors capable of swinging in two-dimensional directions.

In some more specific embodiments, the scanning galvanometer unit includes any one of a two-dimensional scanning MEMS micromirror, a mechanical pendulum mirror, a piezoelectric driven scanning mirror and a voice coil motor driven scanning mirror, but is not limited to this.

In some more specific implementations, the scanning vibrating mirror unit includes a first scanning vibrating mirror and a second scanning vibrating mirror, the first scanning vibrating mirror is at least used to form a scanning image in the X-axis direction, and the second scanning vibrating mirror The scanning galvanometer is at least used to form a scanning image in the Y-axis direction; wherein the first scanning galvanometer and the second scanning galvanometer are both one-dimensional scanning galvanometers.

Preferably, the display unit is selected from a microlens array or a fiber optic plate.

Further, the miniature two-dimensional laser scanning image source further includes: a relay mirror unit, which is at least used to adjust the direction of the optical path of the converged light beam, and make the converged light beam incident to the scanning galvanometer unit.

The embodiment of the utility model also provides a projection system, including the miniature two-dimensional laser scanning image source.

The embodiment of the present invention also provides the application of the miniature two-dimensional laser scanning image source or the projection system in the field of HUD, HMD, VR or AR.

The laser scanning image source is a miniaturized laser image source formed based on a two-dimensional scanning galvanometer. In some more specific implementations, please refer to Figure 2. A miniature two-dimensional laser scanning image source mainly includes a laser light source 1, an optical Lens 2, relay mirror 3, MEMS micromirror 4 and screen 5 for two-dimensional scanning, laser light source 1 can be a semiconductor laser, fiber laser, etc.; RGB three-color lasers need to be used for color image sources, and the spectrum of the laser is narrow. Realize a large color gamut, and its color range can reach 160% NTSC; the optical lens 2 can at least form a converged beam of light emitted by the laser light source 1 and converge it on the screen. The size of the converged spot is the size of the image pixel. The parameters of the optical lens need to be Design according to parameters such as pixel size; the purpose of the relay mirror 3 is to adjust the direction of the optical path, reduce the volume of the system, make the system more compact, and the placement position can be changed; the two-dimensional scanning MEMS micromirror 4 is a A reflector capable of high-speed deflection can realize biaxial deflection. During the working process, it reflects the converging light beam to each pixel position of the image through rapid deflection to form the required pattern; the screen 5 is the carrier of the image; for the HUD, it can directly The image information is projected on the screen observed by the driver (such as the window glass). In applications such as HUD, VR, and AR, a relay screen may be required to carry the image information. The laser has good coherence. When random reflectors such as frosted glass are used When the scattered device is used as a screen, there will be "flare", speckle and other phenomena, and the microlens array (or fiber optic fiber board) as a screen can effectively solve these defects, and can image the image to the human eye very well. The microlens array The design of the laser needs to be designed according to the pixel size and the requirements of the observer, and it is a better laser image source screen.

The principle of laser scanning using a two-dimensional scanning MEMS micromirror: When the light beam emitted from the light source passes through the two-dimensional deflection scanning of the scanning galvanometer, a two-dimensional bright plane will be formed on the imaging screen. At the same time, by modulating the light source (laser) according to the image color information, the brightness and color of the laser beam at any point on this two-dimensional plane can be controlled, so that the position of the laser beam can be controlled by scanning the vibrating mirror, and the laser beam can be controlled by combining the image information. modulation, thereby "drawing" the image point by point on the imaging screen.

During the scanning process of the galvanometer, when the beam is deflected to each pixel point, the laser current is controlled at the same time to obtain the same color as the pixel point. For areas without pattern color information, the laser can be turned off to achieve a completely black state, without unnecessary weak light areas.

The miniature two-dimensional laser scanning image source provided by the utility model has few image source components and high light utilization efficiency; the adopted laser has low power and low power consumption; no additional heat dissipation system is required, the system structure is simple, small in size and light in weight; two-dimensional scanning vibration The mirror is in a resonant state, and the power consumption is low; the laser light source can achieve high contrast and high brightness, so that the image can be observed well in a bright environment, and the two-dimensional scanning MEMS micromirror is used for imaging, and the scanning laser light source can only display the necessary Pixel information, avoiding a small amount of weak light in other areas, can achieve high contrast of image source images, and improve the recognition and clarity of AR, VR, and HUD display information and images.

The utility model utilizes a two-dimensional scanning galvanometer and a laser to produce a small-volume, high-resolution, high-brightness, high-contrast image source, and applies the two-dimensional scanning laser image source to fields such as HUD, VR, and AR.

In the laser scanning image source, the screen adopts microlens array or fiber optic fiber board, which can well transmit the image information to the human eye while avoiding the generation of speckle, and the laser has good monochromaticity, which is easy to be compared with holographic display technology. combined.

It should be understood that the above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present utility model, and its purpose is to enable those familiar with this technology to understand the content of the present utility model and implement it accordingly, and cannot limit the protection of the present utility model. scope. All equivalent changes or modifications made according to the spirit of the utility model shall fall within the protection scope of the utility model.

Claims (8)

1. a kind of micro two-dimensional laser scanning image source, it is characterised in that including：Laser light source, lens unit, scanning galvanometer unit, Display unit and control unit, the lens unit and scanning galvanometer unit are set in turn in the laser light source and display unit Between, the laser light source is at least emitting laser beam；The lens unit at least swashs to emit laser light source Light light beam forms converging beam；The scanning galvanometer unit is at least reflecting the converging beam and be incident on display unit； The display unit, at least to receive scanning galvanometer unit reflection converging beam；Described control unit respectively with laser light Source is connected with scanning galvanometer unit.

2. micro two-dimensional laser scanning image source according to claim 1, it is characterised in that：The laser light source includes that can send out Go out any one in the semiconductor lasers of tri- colors of RGB, optical fiber laser.

3. micro two-dimensional laser scanning image source according to claim 1, it is characterised in that：The scanning galvanometer unit is selected from It can be in the speculum that two-dimensional square is swung up.

4. micro two-dimensional laser scanning image source according to claim 1 or 3, it is characterised in that：The scanning galvanometer unit MEMS micromirror, mechanical pendulum mirror, the scanning mirror of Piezoelectric Driving including two-dimensional scan and appointing in the scanning mirror of voice coil motor driving Meaning is a kind of.

5. micro two-dimensional laser scanning image source according to claim 1, it is characterised in that：The scanning galvanometer unit includes First scanning galvanometer and the second scanning galvanometer, first scanning galvanometer are described at least to form scan image in X-direction Second scanning galvanometer is at least in Y direction formation scan image；Wherein described first scanning galvanometer and the second scanning galvanometer It is one-dimensional scanning galvanometer.

6. micro two-dimensional laser scanning image source according to claim 1, it is characterised in that：The display unit is selected from micro- Lens array or fiber optics plate.

7. micro two-dimensional laser scanning image source according to claim 1, it is characterised in that further include：Relay mirror list Member at least to adjust the light path trend of the converging beam, and makes the converging beam be incident to scanning galvanometer unit.

8. a kind of optical projection system, it is characterised in that including the micro two-dimensional laser scanning picture described in any one of claim 1-7 Source.