WO2013063835A1

WO2013063835A1 - Dlp micro projector

Info

Publication number: WO2013063835A1
Application number: PCT/CN2011/082991
Authority: WO
Inventors: 杨伟梁; 高志强; 赵远
Original assignee: 广景科技有限公司
Priority date: 2011-11-03
Filing date: 2011-11-25
Publication date: 2013-05-10
Also published as: CN202306119U

Abstract

Disclosed is a DLP micro projector, the light source of the device for providing light to the projector being configured as a horizontal device (1) and a vertical device (6). A horizontal collimating lens group (2, 3) and a vertical collimating lens group (4, 5) are respectively provided corresponding to the horizontal device and the vertical device. Two spectroscope glasses (7, 8) for reflecting light of different colours are provided sequentially along the optical path of the vertical collimating lens group. The three coloured light rays emitted by the light source can be mutually parallel and incident on the optical components behind. The DLP micro projector can not only reduce the size of projector, but can also solve the possible problem of low light transmission efficiency due to a reduction in the size of projector.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of digital projection display technology, and more particularly to a DLP pico projector. Background technique

DMD (Dig i ta l Mi cromi rror Dev ice ) is a light modulation device developed by TI Corporation of the United States. It can control the micro-mirror array with extremely high reflectivity and can project the three primary colors (RGB) with the projection optical system. The screen, the projector using this device is generally called DLP (Dig i ta l Light Projector) projector. This technology shows great advantages in terms of flow brightness, video image display and contrast ratio compared to conventional LCD projectors. A DLP-based projection system includes signal reception and processing functions, a DLP projection optomechanical module, and supports an all-digital approach. Elements of the DLP Projector module include a light source, a cooling system, signal modulation DMD devices, and projection optics. A DMD can be simply described as a semiconductor optical switch. Thousands of tiny square lenses are constructed on the hinge structure above the static access memory to form a DMD. Each lens can turn on and off one pixel of light. The hinge structure allows the lens to be tilted between two states, +10 degrees being "on". -10 degrees is "off", when the lenses are not working, they are in a 0 degree "parking" state. The current DLP projector module should be applied to handheld electronic devices, and it is necessary to achieve a small size while maintaining a high light output. In order to achieve a suitable size, in addition to the simplicity and efficiency of the design of the projection light path, The optical path and heat dissipation structure in the optical device also require detailed design, and the production cost of the overall optical machine must also be considered to meet the application of the portable electronic device.

SUMMARY OF THE INVENTION In order to satisfy the application of a projector in a handheld electronic device, one of the objects of the present invention is to provide a DLP micro projector based on a DMD device in order to reduce its size. Another object of the present invention is to provide a DLP micro projector based on a DMD device to solve the problem of reduced light transmission efficiency which may be caused by a reduction in size of the projector. The utility model adopts the following technical solutions to achieve the above object: A DLP micro projector, comprising a light supply device, an optical path conversion device, a DLP light modulator and a projection lens device, the light supply device comprising an LED light source and a vertical alignment a direct lens group, a horizontal collimating lens group and a beam splitting lens group; the LED light source comprises a first color LED chip, a second color LED chip and a third color LED chip, wherein the first color LED chip and the second color LED chip are horizontal Arranging and having a central optical axis of a vertical shape, the central optical axis of the third color LED chip is horizontal and coincides with a central optical axis of the optical path changing device; the central optical axis of the vertical collimating lens group is vertical And the vertical lens group is disposed above the first color LED chip and the second color LED chip for receiving natural light from the first color LED chip and the second color LED chip and homogenizing the light; the horizontal alignment The central optical axis of the lens group is horizontal and coincides with the central optical axis of the third color LED chip for receiving natural light from the third color LED chip and fortifying the light, the transmitted light of the horizontal lens group and the vertical straight The projection light of the lens group vertically intersects; the spectroscopic lens group includes a first dichroic mirror and a second dichroic mirror arranged in sequence, the first dichroic mirror reflecting light of the first color LED chip and transmitting the second LED chip and The light of the third color LED chip, the second dichroic mirror reflects the light of the second color LED chip and transmits the light of the first LED chip and the third color LED chip, to realize the first color LED chip and the second color The light emitted by the LED chip is horizontally reflected into the optical path conversion device, and the light emitted by the third color LED chip is horizontally transmitted to the optical path conversion device. As a further description of the above solution: Preferably, the central optical axis of the vertical collimating lens group and the central optical axis of the first color LED chip, the central optical axis of the second color LED chip or the first color LED chip and the The vertical optical axes at the midpoint of the two-color LED chip connection coincide. Preferably, the central optical axis of the vertical collimating lens group and the vertical optical axis at the midpoint of the line connecting the first color LED chip and the second color LED chip coincide. Preferably, the horizontal collimating lens group and the vertical collimating lens group receive natural light emitted by the LED light source and emit light of approximately parallel light having a divergence of less than 20°. Preferably, the horizontal collimating lens group and the vertical collimating lens group receive natural light emitted by the LED light source and emit light of approximately parallel light having a divergence of less than 15°. Preferably, the optical path conversion device includes a fly-eye lens group, a mirror, a condenser lens, and a prism disposed along the optical path, for receiving light from the light supply device and guiding the same to the DLP optical modulator. The mirror is provided with an angle adjustment device. Preferably, the projection lens device comprises a first lens, a second lens and a third lens arranged along the optical path, the second lens and the third lens being aspherical plastic lenses, and the first lens is a plastic lens. Preferably, the angle between the central optical axis of the fly-eye lens group and the central optical axis of the projection lens group in the optical path conversion device is less than 60°. Preferably, the angle between the central optical axis of the fly-eye lens group and the central optical axis of the projection lens group in the optical path conversion device is less than 45. . Preferably, the DLP optical modulator is a DMD. The beneficial effects that the utility model can achieve by adopting the above technical solutions are:

1. The DLP pico projector according to the present invention can greatly reduce the size of the light supply device due to the unique structure of the light supply device, and if the central optical axis of the fly-eye lens group and the central optical axis of the projection lens group are further Set to a parallel state, the overall size of the DLP pico projector can be greatly reduced.

2. The projection lens set of the DLP micro projector of the present invention adopts a plastic lens, and two of the lenses are aspherical lenses, which not only reduces the length of the projection lens, but also greatly reduces the cost of the lens and reduces the projection. The weight of the lens.

3. The DLP micro projector of the present invention sets the light source to a horizontal state portion and a vertical state portion, respectively, so that the heat dissipation effect is good. DRAWINGS 1 is a schematic structural view of a DLP micro projector according to the present invention. Description of the reference signs:

1-level LED light source, 2-first collimating lens, 3-second collimating lens, 4-third collimating lens, 5-fourth collimating lens, 6-vertical LED light source, 7-first minute Chromatic mirror, 8-second dichroic mirror, 9 - compound eye array lens, 10 - fourth lens, 11 - mirror, 12 - converging lens, 13 - prism, 14-DMD, 15 - first lens, 16 - Two lenses, 17 - third lens. The present invention will be described in detail with reference to the accompanying drawings and preferred embodiments thereof, but it is understood that the scope of the invention is not limited by the specific embodiments. 1 is a schematic structural view of a DLP micro projector according to the present invention. As shown in the drawing, the DLP pico projector includes a light supply device, an optical path conversion device, a DMD 14 and a projection lens device. The light supply device comprises a horizontal LED light source 1, a vertical collimating lens group, a vertical LED light source 6, a horizontal collimating lens group and a spectroscopic lens group. The horizontal LED light source 1 is disposed on a horizontal surface and its central optical axis is vertical. A straight red LED chip and a blue LED chip, the vertical LED light source 6 is a green LED chip whose center optical axis is horizontal and coincides with the central optical axis of the optical path changing device. A vertical collimating lens group is disposed above the horizontal LED light source 1 and includes a first collimating lens 2 and a second collimating lens 3 which are arranged from bottom to top and whose central optical axes coincide, the central optical axis of the vertical collimating lens group The vertical optical axis at the midpoint of the line connecting the red LED chip and the blue LED chip is coincident, and the vertical collimator lens group is required to transmit light with a divergence of less than 15° for receiving natural light from the horizontal LED light source 1 The light is collimated into approximately parallel light, and the specific parameters of the vertical collimating lens group can be calculated by more technical requirements of those skilled in the art. The horizontal collimating lens group is disposed on the right side of the vertical LED light source 6, and includes a fourth collimating lens 5 and a third collimating lens 4 which are arranged from left to right and whose central optical axes coincide, and the central light of the horizontal collimating lens group The axis coincides with the optical axis of the green LED chip, and the transmitted light of the horizontal collimating lens group The projection light of the vertical collimating lens group intersects perpendicularly, and the horizontal collimating lens group is required to have a divergence of transmitted light of less than 15° for receiving natural light from the vertical LED light source 6 and homogenizing the light into approximately parallel light. The specific parameters of the horizontal collimating lens group can be calculated by more technical requirements of those skilled in the art, or can be the same as the parameters of the vertical collimating lens group. The spectroscopic lens group is disposed at the intersection of the transmitted light of the vertical collimating lens group and the horizontal collimating lens group, and includes a first dichroic mirror 7 and a second dichroic mirror 8 disposed in order from top to bottom, wherein, the second The dichroic mirror 8 reflects red light and transmits green light and blue light. The first dichroic mirror Ί reflects blue light and transmits red light and green light, so that the green light emitted by the vertical LED light source 6 can penetrate the first minute in the horizontal direction. The color mirror 7 and the second dichroic mirror 8 are incident on the optical path conversion device, and those skilled in the art can perform corresponding calculations according to the parameters of the collimator lens group to obtain the first dichroic mirror 7 and the second dichroic mirror. The setting angle of 8 is such that the blue light reflected by the first dichroic mirror 和 and the red light reflected by the second dichroic mirror 8 are reflected in the horizontal direction into the optical path converting device. The optical path conversion device includes a fly-eye lens group disposed along the optical path, a mirror 11, a converging lens 12, and a prism 13 for receiving light from the light supply device and guiding it to the DLP light modulator, the fly-eye lens The group includes a compound eye array lens 9 and a fourth lens 10 whose central optical axes are coincident, and the central optical axis of the fly-eye lens group is parallel to the reflected light of the spectroscopic lens group, and the mirror 11 is provided with an angle adjusting device for finely adjusting the reflected light. At the angle, the converging lens 12 and the prism 13 receive the reflected light from the mirror 11 and guide it onto the DMD 14. The optical path conversion device of the present invention replaces the conventional light bar design and reduces the size of the optical path conversion device. The projection lens arrangement is adapted to receive light modulated by the DMD 14 and to project an image, which uses a telecentric optical path design to increase the optical aperture of the projection lens arrangement. The projection lens device includes a first lens 15, a second lens 16, and a third lens 17 disposed along the optical path, wherein the second lens 16 and the third lens 17 are aspherical plastic lenses, which can reduce the length of the lens. Moreover, the first lens 15, the second lens 16, and the third lens 17 are both plastic lenses, which are formed by an injection molding process, which can greatly reduce the cost and the weight of the lens. To further reduce the size of the projector, the central optical axis of the projection lens device can be set to be parallel to the central optical axis of the fly-eye lens group. The above embodiments and the accompanying drawings of the present invention are only one of the preferred embodiments of the present invention, and the present invention is not limited thereto, without departing from the spirit of the present invention. Any changes made by those skilled in the art are within the scope of protection of the present invention.

Claims

Claim

A DLP pico projector comprising a light supply device, an optical path conversion device, a DLP light modulator, and a projection lens device, the light supply device comprising an LED light source, a vertical collimating lens group, a horizontal collimating lens group, and a beam splitting The LED light source comprises a first color LED chip, a second color LED chip and a third color LED chip, wherein the first color LED chip and the second color LED chip are horizontally arranged and the central optical axis thereof is vertical. The central optical axis of the third color LED chip is horizontal and coincides with the central optical axis of the optical path changing device; the central optical axis of the vertical collimating lens group is vertical, and the vertical lens group is disposed at the a color LED chip and a second color LED chip for receiving natural light from the first color LED chip and the second color LED chip and homogenizing the light; the central optical axis of the horizontal collimating lens group is horizontal and The central optical axes of the third color LED chips are coincident for receiving natural light from the third color LED chip and collimating the light, and the transmitted light of the horizontal lens group vertically intersects the projection light of the vertical lens group; The optical lens group includes a first dichroic mirror and a second dichroic mirror arranged in sequence, the first dichroic mirror reflecting light of the first color LED chip and transmitting light of the second LED chip and the third color LED chip, The second dichroic mirror reflects the light of the second color LED chip and transmits the light of the first LED chip and the third color LED chip, so as to realize the horizontal light emitted by the first color LED chip and the second color LED chip The light is reflected into the optical path conversion device, and the light emitted by the third color LED chip is horizontally transmitted to the optical path conversion device.

2. The DLP pico projector according to claim 1, wherein a central optical axis of the vertical collimating lens group and a central optical axis of the first color LED chip and a central optical axis of the second color LED chip Or the vertical optical axis at the midpoint of the first color LED chip and the second color LED chip connection.

The DLP pico projector according to claim 1 or 2, wherein a central optical axis of the vertical collimating lens group and a midpoint of a line connecting the first color LED chip and the second color LED chip are The vertical optical axes coincide.

4 . The DLP pico projector according to claim 1 , wherein the horizontal collimating lens group and the vertical collimating lens group receive light of natural light emitted by the LED light source, and the light emitted by the LED light source has a divergence of less than 20°. Approximate parallel light.

The DLP pico projector according to claim 4, wherein the horizontal collimating lens group and the vertical collimating lens group receive light of natural light emitted by the LED light source, and the light emitted by the LED light source has a divergence of less than 15°. Approximate parallel light.

6. The DLP pico projector according to claim 3, wherein the optical path conversion device comprises a fly-eye lens group, a mirror, a condenser lens, and a prism disposed in sequence along the optical path, for receiving from the light supply device. The light is evenly directed onto a DLP light modulator, which is provided with an angle adjustment device.

7. The DLP pico projector according to claim 6, wherein the projection lens device comprises a first lens, a second lens, and a third lens, which are sequentially disposed along an optical path, the second lens and the third lens As an aspherical plastic lens, the first lens is a plastic lens.

The DLP pico projector according to claim 1 or 5, wherein an angle between a central optical axis of the fly-eye lens group and a central optical axis of the projection lens group in the optical path conversion device is less than 60°.

9. The DLP pico projector according to claim 8, wherein an angle between a central optical axis of the fly-eye lens group and a central optical axis of the projection lens group in the optical path conversion device is smaller than

45°.

The DLP pico projector of claim 1, wherein the DLP light modulator is a DMD.