TFT projection illumination brightening device and projector

Abstract

The utility model discloses a TFT projection illumination brightening device and a projector, the TFT projection illumination brightening device comprises an LED lamp panel and a TFT, a collimating lens group and a polarizing film are arranged between the LED lamp panel and the TFT, a plurality of COB packaged LED light-emitting chips are pasted on the LED lamp panel, a reflecting film and a 1 / 4 wave plate film are sequentially arranged on the surface of the LED lamp panel, and the reflecting film and the 1 / 4 wave plate film are arranged on the surface of the TFT. The reflecting film is located between the LED lamp panel and the 1 / 4 wave plate film, the reflecting face of the reflecting film faces the 1 / 4 wave plate film, and the thickness of the reflecting film and the thickness of the 1 / 4 wave plate film are not larger than the light-emitting face of the LED light-emitting chip. According to the utility model, the reflected ineffective light is subjected to polarization conversion, and then a part of ineffective light is converted into recycled effective light, so that the energy utilization rate is improved and the display brightness is increased under the condition that the cost is not increased too much.

Description

Technical Field

[0001] The utility model relates to the technical field of TFT projection and head-up display, in particular to a TFT projection lighting brightening device and a projector. Background Art

[0002] In a single-LCD projector, light from the LED light source is focused and collimated by an illumination device before illuminating the LCD light valve. One illumination device solution utilizes a light hopper (also known as a "hollow square-cone concentrator") combined with a Fresnel lens (referred to as light hopper illumination, hereinafter referred to). This lighting device is extremely low-cost and simple to manufacture, but it is bulky, and the densely packed LED chips significantly impact heat dissipation. Furthermore, product consistency is limited by the light hopper's material properties and manufacturing precision.

[0003] Another solution for the lighting device is to use a combination of a condenser and a Fresnel lens (hereinafter referred to as condenser lighting). In practice, the cost and lighting efficiency of this lighting device are slightly higher than the above-mentioned light bucket lighting method.

[0004] Because LCD light valves utilize the optical principles of polarization, liquid crystal rotation, and polarization analysis, while LEDs emit natural light, half of the light illuminating the LCD light valve's TFTs is ineffective. This light, incident on the TFTs, generates heat, causing the TFTs to heat up. Therefore, a polarizer is typically added in front of the LCD light valve to reflect the ineffective polarized light. Because this reflected ineffective polarized light remains unused, LCD projection systems suffer from low light efficiency, low energy utilization, and limited brightness. Utility Model Content

[0005] The main purpose of the utility model is to propose a TFT projection lighting brightening device and a projector, which aims to improve energy utilization and increase display brightness without increasing excessive costs by converting the polarization of reflected invalid light and then converting part of the invalid light into reusable valid light.

[0006] To achieve the above-mentioned purpose, the present invention proposes a TFT projection lighting brightening device, comprising: an LED light board and a TFT, a collimating lens group and a polarizing film are arranged between the LED light board and the TFT, a plurality of COB-packaged LED light-emitting chips are affixed to the LED light board, and a reflective film and a 1 / 4 wave plate film are arranged in sequence on the surface of the LED light board, the reflective film is located between the LED light board and the 1 / 4 wave plate film, the reflective surface of the reflective film faces the 1 / 4 wave plate film, and the thickness of the reflective film and the 1 / 4 wave plate film does not exceed the light-emitting surface of the LED light-emitting chip.

[0007] A further technical solution of the present invention is that the collimating lens group and the polarizing film are sequentially arranged between the LED light board and the TFT from front to back.

[0008] A further technical solution of the present invention is that the polarizing film and the collimating lens group are sequentially arranged between the LED light board and the TFT from front to back.

[0009] To achieve the above-mentioned object, the present invention further provides a projector, which includes the TFT projection lighting brightening device as described above.

[0010] The beneficial effects of the TFT projection lighting brightening device and projector of the utility model are:

[0011] 1. The utility model converts the originally reflected invalid light into polarization and reuses it, thereby improving energy utilization and increasing display brightness.

[0012] 2. The utility model increases the light energy output, thereby reducing the light energy absorption and reducing the heat of the system.

[0013] 3. The utility model uses a membrane material with a thickness of only 50 to 300 μm, which is low in cost and saves volume.

[0014] 4. The utility model improves the brightness, cost performance and product competitiveness of the projector. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0016] Figure 1 This is a structural diagram of the first embodiment of the preferred embodiment of the TFT projection lighting enhancement device of the present invention;

[0017] Figure 2 This is a structural diagram of another embodiment of the preferred embodiment of the TFT projection lighting enhancement device of the present invention;

[0018] Figure 3 This is a schematic diagram of light path simulation of a preferred embodiment of the TFT projection lighting enhancement device of the utility model;

[0019] Figure 4 This is a schematic diagram of light path simulation for increasing the number of tracking rays in a preferred embodiment of the TFT projection lighting enhancement device of the present invention;

[0020] Figure 5 This is a schematic diagram of the gap between the reflective film and the quarter-wave plate film 2×4 array LED light-emitting chip;

[0021] Figure 6 It is a schematic diagram of the gap between the reflective film and the 1 / 4 wave plate film 13×19 array LED light-emitting chip.

[0022] Description of Figure Numbers:

[0023] LED light board 1; TFT 2; collimating lens group 3; polarizing film 4; reflecting film 5; 1 / 4 wave plate film 6; LED light-emitting chip 7.

[0024] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0026] A major drawback of LED projectors is limited brightness. With price constraints, simply increasing the power of the light source board is no longer feasible. The transmittance of internal optical components is also difficult to significantly improve, and TFTs inherently have low transmittance. Therefore, given the existing structure and cost considerations, improving brightness and cost-effectiveness is a challenge that needs to be addressed.

[0027] Based on this, the utility model proposes a TFT projection lighting brightening device, which converts the polarization of reflected invalid light and can convert part of the invalid light into reusable effective light, thereby improving energy utilization and increasing display brightness without increasing excessive costs.

[0028] For details, please refer to Figures 1 to 6 A preferred embodiment of the TFT projection lighting brightening device of the present invention includes an LED light board 1 and a TFT2, a collimating lens group 3 and a polarizing film 4 are arranged between the LED light board 1 and the TFT2, a plurality of COB-packaged LED light-emitting chips 7 are affixed to the LED light board 1, and a reflective film 5 and a 1 / 4 wave plate film 6 are arranged in sequence on the surface of the LED light board 1, the reflective film 5 is located between the LED light board 1 and the 1 / 4 wave plate film 6, the reflective surface of the reflective film 5 faces the 1 / 4 wave plate film 6, and the thickness of the reflective film 5 and the 1 / 4 wave plate film 6 is not higher than the light-emitting surface of the LED light-emitting chip 7.

[0029] In one embodiment, the collimating lens group 3 and the polarizing film 4 are sequentially arranged between the LED light board 1 and the TFT 2 from front to back.

[0030] The following combination Figure 1 The first embodiment shown describes the working principle of the TFT projection lighting brightening device of the present invention.

[0031] 1. LED light board 1 is mounted with several COB-packaged LED chips 7. LED chips 7 emit light a, which is collimated by collimating lens assembly 3 and outputs light beam b. This light is then split into two parts by polarizing film 4: transmitted light c and reflected light d. Transmitted light c is evenly illuminated onto TFT 2.

[0032] 2. The light beam d reflected by the polarization mode is converted into light beam e after passing through the reverse collimating lens group 3. Light beam e has a certain diffusion angle, part of the light returns to the LED chip area, and the other part reaches the area outside the chip.

[0033] 3. Arrange the reflective film 5 and the 1 / 4 wave plate film 6 in sequence on the surface of the LED light board 1. The reflective film 5 is located between the LED light board 1 and the 1 / 4 wave plate film 6, with the reflective surface facing the 1 / 4 wave plate film 6. The thickness of the reflective film 5 and the 1 / 4 wave plate film 6 is not higher than the light-emitting surface of the LED chip.

[0034] 4. Part of the light in the beam e first passes through the 1 / 4 wave plate film 6, generating a 1 / 4 phase difference, and then enters the reflecting surface of the reflective film 5. After being reflected by the reflective film 5, it passes through the 1 / 4 wave plate again, generating a total phase difference of 1 / 2. Therefore, the polarization direction is rotated 90°, and the reflected light f is obtained.

[0035] 5. The f light contains some polarized light with the same polarization as the c light. Therefore, after passing through the collimating lens group 3, the f light obtains the collimated g light. After passing through the polarizing film 4, the transmitted h light has the same polarization direction as the c light. The h light also evenly illuminates TFT2. Compared with the c light, it is a newly added illumination light, so it increases the illumination flux and improves the brightness of the system.

[0036] As another implementation scheme, the polarizing film 4 and the collimating lens group 3 can also be arranged in sequence from front to back between the LED light board 1 and the TFT2. Its working principle is the same as the first implementation scheme, except that the polarizing film 4 is moved in front of the collimating lens group 3.

[0037] In this embodiment, the reflective film 5 and the 1 / 4 wave plate film 6 are processed by die cutting or laser cutting to remove the parts that may interfere with the LED light-emitting chip 7, the lamp board positioning hole, the mounting hole, the anti-fool groove, etc., and finally the effective area remains.

[0038] The beneficial effects of the TFT projection lighting brightening device of the utility model are:

[0039] 1. The utility model converts the originally reflected invalid light into polarization and reuses it, thereby improving energy utilization and increasing display brightness.

[0040] 2. The utility model increases the light energy output, thereby reducing the light energy absorption and reducing the heat of the system.

[0041] 3. The utility model uses a membrane material with a thickness of only 50 to 300 μm, which is low in cost and saves volume.

[0042] 4. The utility model improves the brightness, cost performance and product competitiveness of the projector.

[0043] To achieve the above objectives, the present invention further provides a projector, which includes the TFT projection lighting enhancement device as described in the above embodiment. The structure and working principle of the TFT projection lighting enhancement device have been described in detail above and will not be repeated here.

[0044] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made based on the contents of the present invention specification and drawings, or direct / indirect application in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A TFT projection lighting brightness enhancement device, characterized in that: include: An LED light board and a TFT, a collimating lens group and a polarizing film are arranged between the LED light board and the TFT, a number of COB-packaged LED light-emitting chips are affixed to the LED light board, and a reflective film and a 1 / 4 wave plate film are arranged in sequence on the surface of the LED light board, the reflective film is located between the LED light board and the 1 / 4 wave plate film, the reflective surface of the reflective film faces the 1 / 4 wave plate film, and the thickness of the reflective film and the 1 / 4 wave plate film is not higher than the light-emitting surface of the LED light-emitting chip.

2. The TFT projection lighting brightness enhancement device according to claim 1, characterized in that: The collimating lens group and the polarizing film are sequentially arranged between the LED light board and the TFT from front to back.

3. The TFT projection lighting brightness enhancement device according to claim 1, characterized in that: The polarizing film and the collimating lens group are sequentially arranged between the LED light board and the TFT from front to back.

4. A projector, characterized in that: The projector includes the TFT projection lighting brightening device according to any one of claims 1 to 3.

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