CN112305841A

CN112305841A - DLP projection system and vehicle

Info

Publication number: CN112305841A
Application number: CN201910708013.7A
Authority: CN
Inventors: 刘路青; 仇润; 华圣熙
Original assignee: Changzhou Xingyu Automotive Lighting Systems Co Ltd
Current assignee: Changzhou Xingyu Automotive Lighting Systems Co Ltd
Priority date: 2019-08-01
Filing date: 2019-08-01
Publication date: 2021-02-02

Abstract

The present invention provides a DLP projection system and a vehicle, wherein the DLP projection system includes: a light source; the optical piece module is used for processing the light emitted by the light source to obtain an incident beam; the binary diffraction device is perpendicular to the incident beam and is used for shaping and homogenizing the incident beam; the surface of the DMD chip is parallel to the binary diffraction device, and the DMD chip is used for modulating the shaped and homogenized light so as to form a pattern in a projecting mode. The invention realizes two functions of shaping and light homogenizing through the binary diffraction device, can reduce the number of optical elements, reduce the design difficulty of an optical structure, simultaneously can reduce the size of the optical structure, and improve the miniaturization and integration of the whole structure, thereby reducing the cost, reducing the whole space occupancy rate and improving the applicability of the system.

Description

DLP projection system and vehicle

Technical Field

The invention relates to the technical field of vehicles, in particular to a DLP projection system and a vehicle.

Background

With the development of economy in China, the popularization rate of automobiles is higher and higher, the road traffic condition in China is more complex, and the probability of traffic accidents is higher, so that the safety performance of automobiles is more and more emphasized by people. As a main part of automobile safety, the functions of the automobile lamp are not limited to lighting itself, and the automobile lamp is gradually developed toward multi-functionalization. Among them, the projection of the signal of the car lamp is one of the important development directions of the car lamp. The automobile lamp signal projection system can realize automobile driving illumination, simultaneously form symbols and patterns on the ground to prompt drivers and pedestrians, and form information interaction between people and vehicles and between vehicles so as to improve driving safety.

At present, a DLP (Digital light Processing) technology is mostly adopted in a signal projection system of an automobile lamp, and has the advantages of high response speed, high pixels and the like. However, DLP technology also has certain limitations, and requires that the distribution of light emitted from a light source on the chip surface should be as uniform as possible and consistent with the chip surface size, which puts high demands on collimating, light-homogenizing and shaping optical components in the system. Generally, most of adopted optical elements can only realize the transformation of basic spherical waves or plane waves, and a plurality of optical elements are needed to finish two functions of shaping and dodging of light beams, so that the number of the optical elements in the system is large, and the space of the automobile lamp is limited, thereby bringing great difficulty to the design and production work of an automobile lamp signal projection system.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the art described above. Therefore, an object of the present invention is to provide a DLP projection system, which can implement two functions of shaping and dodging through a binary diffraction device, reduce the number of optical elements, reduce the design difficulty of an optical structure, and at the same time, reduce the size of the optical structure, and improve the miniaturization and integration of the whole structure, thereby reducing the cost, reducing the overall space occupancy rate, and improving the applicability of the system.

A second object of the invention is to propose a vehicle.

To achieve the above object, an embodiment of the present invention provides a DLP projection system, including: a light source; the optical piece module is used for processing the light emitted by the light source to obtain an incident beam; the binary diffraction device is perpendicular to the incident light beam and is used for shaping and homogenizing the incident light beam; and the surface of the DMD chip is parallel to the binary diffraction Device, and the DMD chip is used for modulating the shaped and homogenized light so as to form a pattern by projection.

According to the DLP projection system provided by the embodiment of the invention, the light emitted by the light source is processed through the optical element module to obtain the incident light beam, the binary diffraction device is used for shaping and dodging the incident light beam, and then the light after shaping and dodging is modulated through the DMD chip to form the pattern by projection, so that the two functions of shaping and dodging are realized through the binary diffraction device, the number of optical elements can be reduced, the design difficulty of an optical structure is reduced, the size of the optical structure can be reduced, the miniaturization and the integration of the whole structure are improved, the cost can be reduced, the overall space occupancy rate is reduced, and the applicability of the system is improved.

In addition, the DLP projection system proposed according to the above embodiment of the present invention may further have the following additional technical features:

further, the DLP projection system according to the embodiment of the present invention further includes a mirror and a lens, wherein the light reflected by the DMD chip is reflected by the mirror, and a pattern is formed by the lens.

According to an embodiment of the present invention, the Light source is a monochromatic LED (Light Emitting Diode), and the optical module is a collimating lens group for collimating Light emitted from the monochromatic LED.

According to an embodiment of the present invention, the light source is a laser diode, and the optical module is a beam expanding lens group, and the beam expanding lens group is configured to expand light emitted by the laser diode.

According to one embodiment of the invention, the binary diffraction device is subjected to etching design according to input light intensity and phase distribution, output light intensity distribution, and the spatial phase difference between the binary diffraction device and the DMD surface.

In order to achieve the above object, a second embodiment of the present invention provides a vehicle including the DLP projection system of the first embodiment.

According to the vehicle provided by the embodiment of the invention, by adopting the DLP projection system provided by the embodiment of the invention, the number of optical parts can be reduced, the difficulty in designing an optical structure can be reduced, and the information interaction between people and the vehicle and between the vehicle and the workshop can be realized, so that the cost can be reduced, and the driving safety can be improved.

Drawings

FIG. 1 is a schematic structural diagram of a DLP projection system according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the optical path of a DLP projection system with a single-color LED as the light source according to an embodiment of the present invention;

FIG. 3 is a schematic diagram of an optical path of a DLP projection system with a laser diode as a light source according to an embodiment of the present invention;

FIG. 4 is a flow chart of a phase distribution design method for a binary diffractive device in accordance with one embodiment of the present invention;

FIG. 5 is an input intensity profile of a MATLAB-fitted binary diffractive device according to one embodiment of the present invention;

FIG. 6 is a light intensity profile of a MATLAB-fitted DMD surface, in accordance with one embodiment of the present invention.

Detailed Description

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

Fig. 1 is a schematic structural diagram of a DLP projection system according to an embodiment of the present invention.

As shown in fig. 1, the DLP projection system according to the embodiment of the present invention includes a light source 10, an optical module 20, a binary diffraction device 30, and a DMD chip 40. The optical module 20 is configured to process light emitted from the light source 10 to obtain an incident light beam; the binary diffraction device 30 is perpendicular to the incident beam, and the binary diffraction device 30 is used for shaping and homogenizing the incident beam; the surface of the DMD chip 40 is parallel to the binary diffraction device 30, and the DMD chip 40 is used to modulate the shaped and homogenized light to form a pattern by projection.

Further, as shown in fig. 1, the DLP projection system according to the embodiment of the present invention may further include a mirror 50 and a lens 60. The light reflected by the DMD chip 40 is reflected by the mirror 50, and then patterned by the lens 60.

In one embodiment of the present invention, as shown in fig. 2, the light source 10 may be a monochromatic LED, and the optical module 20 may be a collimating lens group, and the collimating lens group may be configured to collimate light emitted from the monochromatic LED, that is, the collimating lens group may convert divergent light emitted from the monochromatic LED into parallel light beams to obtain parallel incident light beams.

In another embodiment of the present invention, as shown in fig. 3, the light source 10 may be a laser diode, the optical module 20 may be a beam expanding lens group, and the beam expanding lens group may be configured to expand light emitted from the laser diode, that is, the beam expanding lens group may be configured to expand a diameter of a parallel light beam emitted from the laser diode, so as to obtain a parallel incident light beam with a larger diameter.

In one embodiment of the present invention, the binary diffractive device 30 can be designed according to the input light intensity and phase distribution, the output light intensity distribution, and the spatial phase difference between the binary diffractive device 30 and the DMD surface. Wherein the input phase profile is related to the optical path from the light source 10 to each point on the surface of the binary diffractive device; the output light intensity distribution can be uniform light spots conforming to the shape of the DMD chip, and can also be other light shapes formed according to the requirement; the spatial phase difference of the binary diffractive device from the DMD surface is related to the relative position of the binary diffractive device 30 and the DMD surface and the wavelength of the incident light.

In an embodiment of the present invention, the binary diffraction device 30 may be a micro-nano processing technology to etch a relief structure on the surface, and the designed phase distribution is realized by the different thicknesses of different positions on the surface, so as to realize the shaping and light-homogenizing treatment of the incident light beam. The shaping and the light homogenizing treatment of the incident light beams are realized through the binary diffraction device, and the miniaturization and the integration of the system can be improved.

Further, as shown in fig. 4, the phase distribution designing method of the binary diffraction device 30 includes: inputting the light intensity and the phase distribution of incident light as initial cycle data into an input surface of the binary diffraction device to obtain the amplitude and the phase distribution of the input surface; carrying out forward diffraction transformation on the amplitude and phase distribution of the input surface to obtain the amplitude and phase distribution of the output surface of the binary diffraction device; replacing the calculation result by the target amplitude, namely replacing the amplitude of the output surface by the target amplitude to obtain the amplitude of the output surface after replacement, and simultaneously keeping the phase distribution of the output surface unchanged; carrying out reverse diffraction transformation on the amplitude of the output surface after replacement to obtain the amplitude and phase distribution of the reverse calculation input surface; replacing the calculation result by the input amplitude, namely replacing the input surface amplitude obtained by reverse calculation by the input amplitude, and keeping the phase distribution obtained by reverse calculation unchanged; and repeating the steps, and calculating the phase difference between the input surface phase and the initial incident surface phase at the moment after the circulation is finished to obtain the phase distribution of the binary diffraction device.

Wherein, the light intensity distribution of the incident light can be obtained by optical fitting or actual measurement of the light path; since the incident light is parallel light or approximately parallel light, the incident light can be regarded as a plane wave, and thus, it is possible to obtain an initial phase distribution of 0.

Further, the phase distribution design method of the binary diffraction device 30 specifically includes: after the light intensity and the phase distribution of the incident light are input, the two-dimensional Fourier transform can be carried out on the light intensity and the phase distribution of the input surface of the binary diffraction device, the light intensity and the phase distribution are multiplied by a diffraction function after the Fourier transform, and then the Fourier inverse transform is carried out, so that the light intensity and the phase distribution of the output surface of the binary diffraction device can be obtained; keeping the phase distribution of the output surface unchanged, and replacing the light distribution of the output surface with the designed light distribution of the surface of the DMD chip, wherein the designed light distribution of the surface of the DMD chip is uniform; carrying out Fourier inverse transformation on the light intensity and phase distribution of the output surface after replacement, dividing by the diffraction function after Fourier inverse transformation, and then carrying out Fourier transformation to obtain the light intensity and phase distribution of the reverse calculation input surface; keeping the phase distribution of the input surface obtained by reverse calculation unchanged, and replacing the light intensity distribution of the input surface obtained by reverse calculation with the light intensity distribution of the incident light; and repeating the steps, comparing the light intensity distribution on the surface of the DMD chip obtained by calculation in each circulation with a design value, finishing the circulation when the variance is less than 5% of the design value, and then reversely calculating the phase distribution of the input surface and the initial phase distribution, namely the difference of the phase distribution of the incident light is the phase distribution of the binary diffraction device.

Wherein, the diffraction function can be determined by the coordinates of the surface points of the binary diffraction device, the coordinates of the surface points of the DMD chip, the relative positions of the binary diffraction device and the DMD chip, and the wavelength of the light wave of the incident light.

In one embodiment of the present invention, after the design of the phase distribution of the binary diffractive device is completed, the relative positions of the binary diffractive device 30 and the DMD chip 40 in the optical path may be determined. The phase distribution of the binary diffraction devices corresponds to the above relative positions, that is, each phase distribution manner of the binary diffraction devices corresponds to the relative positions of one binary diffraction device 30 and the DMD chip 40 in the optical path, and if the above relative positions are modified, the phase distribution of the binary diffraction devices needs to be redesigned.

Further, after determining the relative positions of the binary diffractive device 30 and the DMD chip 40 in the optical path, referring to fig. 5 and 6, the binary diffractive device 30 may convert the incident light into light required by design to be irradiated on the surface of the DMD chip. Specifically, the binary diffractive device 30 can shape and homogenize the incident light beam, for example, the radiation beam with large divergence and poor uniformity of light intensity emitted from the monochromatic LED light source can be transformed into a uniform and symmetrical light beam to irradiate on the surface of the DMD chip, so as to form a uniform light spot with a size of 2: 1.

Further, after the binary diffraction device 30 converts the incident light into the light required by design and irradiates the light on the surface of the DMD chip 40, the DMD chip 40 may control the micro mirror array switches in the DMD chip 40 according to the input pattern signal, so that the light beam irradiated on the on-state micro mirrors is deflected by 24 °, and after being reflected by the mirrors, the light beam irradiated on the off-state micro mirrors forms a pattern through the lens, and is reflected to the absorption surface. For example, a DMD chip for vehicle signal projection is composed of an array of millions of micro mirrors, each of which has a hinge structure, and can control the mirror to switch between an on state of +12 ° and an off state of-12 °, so that after light emitted from a light source is reflected by the surface of the DMD chip, only the light reflected by the on micro mirror can be reflected by the mirror and then form a pattern through the lens, and the light reflected by the off micro mirror is absorbed, thereby forming a specific pattern.

According to the DLP projection system provided by the embodiment of the invention, the light emitted by the light source is processed by the optical element module to obtain the incident light beam, the binary diffraction element is used for shaping and dodging the incident light beam, and the light after shaping and dodging is modulated by the DMD chip to project a pattern, so that the two functions of shaping and dodging are realized by the binary diffraction element, the number of the optical elements can be reduced, the design difficulty of an optical structure is reduced, the size of the optical structure can be reduced, the miniaturization and the integration of the whole structure are improved, the cost can be reduced, the overall space occupancy rate is reduced, and the applicability of the system is improved.

The invention further provides a vehicle corresponding to the embodiment.

The vehicle provided by the embodiment of the invention comprises the DLP projection system provided by the embodiment, and the specific implementation manner of the vehicle can refer to the embodiment.

In an embodiment of the present invention, an illumination signal system of a vehicle, for example, an ADB (Adaptive Driving Beam) may adopt the DLP projection system proposed in the above embodiment, and may form a pattern projection on the ground while implementing illumination, so as to implement information interaction between people and vehicles and between vehicles and workshops, thereby improving Driving safety.

According to the vehicle provided by the embodiment of the invention, by adopting the DLP projection system provided by the embodiment of the invention, the number of optical parts can be reduced, the design difficulty of an optical structure is reduced, and the information interaction between people and the vehicle and between the vehicle and the workshop is realized, so that the cost can be reduced, and the driving safety is improved.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.

Claims

1. A DLP projection system, comprising:

a light source;

the optical piece module is used for processing the light emitted by the light source to obtain an incident beam;

the binary diffraction device is perpendicular to the incident light beam and is used for shaping and homogenizing the incident light beam;

the surface of the DMD chip is parallel to the binary diffraction device, and the DMD chip is used for modulating the shaped and homogenized light so as to form a pattern in a projecting mode.

2. The DLP projection system according to claim 1, further comprising a mirror and a lens, wherein the light reflected by said DMD chip is reflected by said mirror and a pattern is formed by said lens.

3. The DLP projection system according to claim 1 or 2, wherein said light source is a monochromatic LED and said optical module is a collimating lens group for collimating light emitted from said monochromatic LED.

4. The DLP projection system according to claim 1 or 2, wherein said light source is a laser diode, and said optical module is a beam expanding lens group, said beam expanding lens group being configured to expand light emitted from said laser diode.

5. The DLP projection system according to claim 1 or 2, wherein the binary diffractive device is etched according to the input light intensity and phase distribution, the output light intensity distribution, the spatial phase difference between the binary diffractive device and the DMD surface.

6. A vehicle comprising the DLP projection system of any of claims 1 to 5.