A light source device for a misregistration light cone projector

Abstract

A kind of light source device of staggered light reflection cone projector, belong to optical and structural field;Structure includes: LED face array board, peripheral inner reflection cylinder, heat sink, LED microlens or staggered light reflection cone array;Basic installation relationship is: LED lamp pearl is installed on LED face array PCB board;Staggered light reflection cone array is installed on LED face array PCB board, light reflection cone light inlet is connected with LED lamp pearl, light exit surface is connected with the light path of projector engine, can be directly connected with LCD, dlp display light valve;Staggered light reflection cone array is spliced by 4-20 light reflection cone strips;Each light reflection cone strip is staggered arrangement, corresponding LED lamp pearl arrangement is also staggered;The connecting convex card of the coplanar plate and unit plate of light reflection cone strip and the twisted clamping of via are matched or directly bonded, welded.

Description

Technical Field

[0001] This invention belongs to the field of optical-electronic technology; more precisely, it is a device that greatly enhances the brightness of the optical engine of a projector with low collimation requirements. Background Technology

[0002] The development of projectors has gone through three main stages: CRT projection technology, LCD projection technology, and the more recently developed DLP projection technology. The core of a projector includes three main parts: the projector structure, the optical engine (including the lens assembly), and the electrical control and interface. A crucial component of the optical engine is the light source.

[0003] LCD (Liquid Crystal Display) projectors: In recent years, LED light sources have been widely used in projectors. A single multi-core LED light source is covered with an aspherical lens, expanded and shaped, and then projected onto a light valve; this is widely used in small projectors. The light source for a single-chip color LCD projector is relatively simple. Specifically, dozens of white LED chips arranged together are converged by an aspherical lens and then shaped by a lens, or directly reflected by a funnel-shaped reflector, before being projected onto the LCD's light valve display panel, and then projected onto the screen by a lens assembly.

[0004] Currently, the problems with single-chip color LCD projector light sources are: screen brightness uniformity and insufficient brightness. This is because the reflections from aspherical lenses and funnel-shaped reflectors are not uniformly distributed in the spatial solid angle. On the other hand, the light emission ratios of the center and corners of the projector lens assembly are different, with the center often having a higher light emission ratio. These two factors combined cause the problem of screen brightness uniformity, where the brightness in the center is often greater than that in the corners, and the brightness in the edge area is greater than that in the corner area. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies, solve the problems of screen brightness uniformity and insufficient brightness, make the center brightness of the screen close to the corner brightness, and further improve the efficiency and layout of the light source, arranging as many LED beads as possible within the allowable range of heat generation.

[0006] The features of this invention are: providing a simple and low-cost reflective cone structure and a staggered arrangement; and using uniform or non-uniform arrangement to improve the brightness uniformity of the projected image (the brightness of the central area is greater than that of the corner areas), so as to achieve the unity of brightness and uniformity.

[0007] The content of this invention:

[0008] The present invention provides a staggered reflector cone projector light source device; the structure includes: an LED array plate, an outer inner reflector cylinder, a heat sink, and an LED microlens or a staggered reflector cone array;

[0009] The basic installation relationship is as follows:

[0010] LED beads are mounted on an LED array PCB board, and the back of the LED array PCB board is covered with a heat sink. A staggered reflector array is mounted on the LED array PCB board. The staggered reflector array is composed of many reflectors arranged in a staggered square array. The light inlet (small opening) of the reflector is connected to the LED beads, and the LED beads are located at the center of the light inlet of the reflector. An outer inner reflector tube is fitted around the staggered reflector array. The height of the outer inner reflector tube is longer than (exceeds) the light outlet of the reflector, so there is a distance between the light outlet surface of the outer inner reflector tube and the light outlet of the reflector.

[0011] Basic principles explained:

[0012] The light emitted by the LED beads on the LED array PCB board mounted on the heat sink is reflected and shaped multiple times by the inner wall of the reflector cone of the LED microlens or reflector cone array (the solid angle of the outgoing integrating sphere is greatly reduced). After being emitted from the light outlet of each reflector cone, it is reflected again by the outer inner reflector cylinder (or the reflector cone array can use the LED microlens focusing mode) and emitted from the light-emitting surface of the reflector cone array. After the light-emitting surface is connected to the optical path of the projector engine, it illuminates the display light valve of (LCD, DLP).

[0013] The key technology of this invention lies in: using the staggered arrangement of microlenses or reflective cone arrays to obtain the uniformity of illuminance at the light-emitting surface, which is used to reflect the emitted light.

[0014] Its characteristics are as follows: the staggered reflective cone array is composed of multiple (4-30) reflective cone strips spliced ​​together, forming 2-15 pairs; the structure of the reflective cone strip includes a common panel and unit panels. The common panel is rectangular in shape, with two pieces placed opposite each other, and their long sides are parallel, with an angle between the normals of the two sides between 3-20 degrees; the unit panels are generally trapezoidal in shape, with 4-40 pieces forming 2-20 pairs, and their base sides are parallel to each other, with an angle between the normals of the two sides between adjacent pieces placed opposite each other between 3-20 degrees; the unit panels and the common panel are in a perpendicular planar position relationship; within the same reflective cone strip, there are multiple rows A row of reflective cones, each reflective cone is a four-sided pyramid structure formed by two unit plates and two common panels; the connecting protrusions of the common panels and unit plates of the reflective cone strips are tightly fitted with the twisted clamps of the through holes (the protrusions are twisted and deformed and then clamped at the edge of the through holes), or they are directly bonded or welded to complete the formation of the reflective cone strips; the staggered reflective cone array can be spliced ​​together by bonding or welding the individual reflective cone strips (the unit plates and common panels can be independent plates, or multiple unit plates, or multiple common panels can be bent to form reflective cone strips or directly bent into a staggered reflective cone array).

[0015] The key advantage of this technology is:

[0016] The use of a staggered reflector array ensures uniform illumination on the light-emitting surface. Each reflector's inlet connects to an LED chip, and the light-emitting surface is located in front of the reflector's outlet. The optical axis is centered on and perpendicular to the light-emitting surface. The light-emitting surface connects to the projector engine's optical path and can also be directly connected to the light valves of LCD and DLP displays. The staggered arrangement means that, regardless of whether viewed along the x or y direction, any two adjacent rows or columns are not aligned along the x or y direction, or are misaligned. Alternatively, any two adjacent reflector strips have their reflectors staggered along the x or y direction. If the reflectors of the reflector strips are uniformly arranged, and the exit width of the reflector is one period length, then there are N reflector periods on the reflector strip. The staggered arrangement means that any two adjacent reflector strips are staggered by about half a period (the staggered arrangement is beneficial for the staggered reflector array, as the differences in the output light integrating spheres emitted by each LED can be complementary). The LED beads are also arranged in a staggered manner;

[0017] Background optical technology statement:

[0018] The reflector cone has a focusing effect: (small entrance, large exit) The reflection of the reflector cone is similar to the refraction of the microlens, causing the divergence angle of the integrating sphere of the emitted light from the LED to converge (i.e., tend to decrease), meaning it can concentrate more light along the optical axis (perpendicular to the direction directly in front of the light-emitting surface). Firstly, when each LED is covered with an LED microlens or reflector cone, the final solid angle of each LED is limited, generally (90% energy distribution: and defining the direction of maximum light flux density as the center direction of emission; deviating from this direction will reduce the light flux density, showing a gradual trend) half-angle of 10 degrees to... Within a 20-degree range, positions farther from the LED array PCB board can receive more light from the LEDs, resulting in uniform illumination at that location. Conversely, the closer the distance, the fewer LEDs receive light; at even closer distances, only a small number (less than four) of LEDs receive light, making uniform illumination difficult. Therefore, the closest distance must ensure that the area projected onto the light-emitting surface by a single reflector is between 1 / 30 and 1 / 5 of the total area of ​​the reflector for more uniform illumination. Thus, maintaining a significant distance between the light-emitting surface and the LED array PCB board is crucial to achieving the required uniformity in the area entering the optical engine.

[0019] *Furthermore: To overcome the common defect of excessively high brightness in the center area of ​​projectors, the density of the reflector cones (corresponding to LED beads) on the reflector cone strip can be selected in two ways: one is a uniform linear distribution, and the other is a non-uniform non-linear distribution.

[0020] One non-linear distribution structure (where the center direction of the emitted light cones points to the optical axis, only the density of the light cones varies): the density is lowest in the central region of the light cone strips (maximum spacing), and increases towards the ends (decreasing spacing), showing a gradual trend. Thus, starting from the center of the light cone array, the density of the light cones increases in any direction away from the center, resulting in a relative increase in illuminance in the corner areas. The corner areas of the light-emitting surface have the highest illuminance, ensuring a consistent brightness across the projected image. Similarly, the LED density of a variable-density LED array panel varies in the same way; the density of the light cones increases in any direction away from the center, resulting in a relative increase in illuminance in the corner areas, thus creating a uniform illumination area at the light-emitting surface.

[0021] Another nonlinear distribution structure (the emission center directions of the reflective cones are different, and the emission center directions of the reflective cones in the corner areas converge in the center area of ​​the light-emitting surface): The nonlinearity of the orientation angle of each reflective cone is that the center direction of the energy flux density of the light emitted from the reflective cone in the central area is perpendicular to the light-emitting surface; while the reflective cones that are away from the central area, the closer they are to the corner areas of the reflective cone array, the more the emission center direction of the energy flux density of the reflective cone points to the area of ​​the light-emitting surface that is closer to the center (with a light converging effect). In this case, the emission light axis (equivalent to the center direction of the energy flux density) of each reflective cone in the reflective cone array will also gradually shift towards the center direction of the light-emitting surface as it moves away from the central area of ​​the reflective cone array; in this case, the array spacing of the LED chips on the LED array PCB board (which is also the spacing at the entrance of the reflective cone array) is greater than the spacing at the exit of the reflective cone array.

[0022] *Further: The reflective cone density can be a hollow reflective or a solid transparent medium; a square pyramid, a multi-faceted pyramid, or a cone are all acceptable.

[0023] *Furthermore: The unit panels of the reflective cone array can be independent flat panels, or bent panels folded in pairs; or multiple (2-20) common panels connected end to end to form a whole panel, which is then folded along each fold line to form the common panel connection of the reflective cone array, thus avoiding further welding or bonding work.

[0024] The technological advancement of this invention lies in: providing a solution to the problems of screen brightness uniformity, insufficient brightness, and dispersed heat generation; and also providing a simple staggered reflective cone array structure, simplifying the structure and process, and reducing costs. Attached Figure Description

[0025] The present invention will be further described below with reference to a preferred embodiment;

[0026] [ Figure 1 Schematic diagram of the light source device for a staggered reflector cone projector.

[0027] [ Figure 2 ] Explosion diagram of the light source device of the misaligned reflector projector.

[0028] [ Figure 3 A schematic diagram of the unit strip assembly structure of the reflective cone.

[0029] Label Explanation:

[0030] (1) LED array PCB board

[0031] (1-1) LED beads

[0032] (2) Heat sink

[0033] (3) Outer inner reflector tube

[0034] (4) Offset reflective cone array

[0035] (5) Reflective cone strips

[0036] (5-1) Common panel

[0037] (5-2) Unit board

[0038] (5-3) Reflector cone (hollow inside)

[0039] (5-4) Reflector entrance

[0040] (5-5) Light outlet of the reflector cone

[0041] (5-6) Convex card

[0042] (5-7) Via

[0043] (9) Light-emitting surface

[0044] (10) Optical axis

[0045] (11) Connecting bracket

[0046] (12) Cooling fan Detailed Implementation

[0047] like[ Figure 1 ]、[ Figure 2 As shown:

[0048] The light source device of the staggered reflector projector consists of an LED array PCB board (1), a heat sink (2), an outer inner reflector cylinder (3), and a staggered reflector array (4); combined with Figure 2 The front view of the lower reflector cone can be clearly seen; the LED array PCB board (1) is composed of LED beads (1-1); the staggered reflector cone array (4) is composed of staggered reflector cone strips (5) (8 strips in the figure); the outer inner reflector cylinder (3) surrounds the staggered reflector cone array (4), and the light-emitting surface (9) of the outer inner reflector cylinder (3) is connected to the optical path of the projector engine, which can be directly connected to the (LCD, DLP) display light valve; the direction of the optical axis (10) is parallel to the vertical direction of the LED array PCB board (1), the main light-emitting direction of the (5-3) reflector cone, and the direction of the central axis of symmetry of the outer inner reflector cylinder (3). The function of the outer inner reflector cylinder (3) is to reflect the light back to the area of ​​the light-emitting surface (9) so that all the light enters the optical engine.

[0049] The heat sink (2) is connected to the cooling fan (12) via the connecting bracket (11) and blows air along the direction of the blades to cool it.

[0050] like[ Figure 2 ]and[ Figure 3 As shown:

[0051] The reflective cone (5) consists of a common panel (5-1) and unit panels (5-2). The common panel (5-1) is rectangular in shape and has a common through hole (5-7). Two panels are placed opposite each other with their long sides parallel, and the included angle between the normals of the two sides is between 3 and 20 degrees. The unit panels (5-2) are generally trapezoidal in shape, and there are 4 to 30 units in total, forming 2 to 15 pairs. The side is machined with at least two protruding clips (5-6), and the bottom edges are parallel to each other. The angle between the normals of the two adjacent pieces is between 3 and 20 degrees. The unit plate (5-2) and the common panel (5-1) are in a perpendicular planar position relationship. The protruding clips (5-6) of the unit plate are inserted into the through holes (5-7) of the common panel (5-1). Since the length of the protruding clips (5-6) is much greater than the thickness of the through holes (5-7), the front part of the protruding clips (5-6) will protrude from the through holes (5-7). After bending or twisting the protruding clips (5-6), they are locked to the edge of the through holes (5-7), thus locking the unit plate and the common panel (5-1) together. The insertion and installation between the protruding clips (5-6) and the through holes (5-7) can be achieved by slightly over-opening the angle between the two common panels (5-1) on the left and right sides, thereby increasing the distance between the common panels (5-1) and facilitating the insertion of the unit plate (5-2).

[0052] In the same reflective cone strip (5), there are multiple reflective cones (5-3) arranged in a row. Each reflective cone (5-3) is a four-sided pyramid structure formed by two unit plates (5-2) and two common plates (5-1). The light inlet (5-4) (small end) of each reflective cone is connected to the LED lamp bead, and the light outlet (5-5) (large end) of the reflective cone faces the light-emitting surface.

[0053] The reflective cones (5-3) of two adjacent reflective cone strips (5) are misaligned, that is, the splicing gap between the reflective cones (5-3) of the same reflective cone strip (5) is located at the middle of the bottom edge of the reflective cone (5-3) of the other reflective cone strip (5); and the alignment of the adjacent two rows of LED beads on the corresponding LED array PCB board is also misaligned.

Claims

1. A staggered reflector cone projector light source device; comprising: LED array panel, outer inner reflector cylinder, heat sink, LED microlens or staggered reflector cone array; The basic installation relationship is as follows: LED beads are mounted on the LED array PCB board, and the back of the LED array PCB board is covered with heat sinks; staggered reflector arrays are mounted on the LED array PCB board, with the light inlets of the reflectors connected to the LED beads, so that the LED beads are located at the center of the light inlets of the reflectors; an outer inner reflector tube is fitted around the staggered reflector array, and the height of the outer inner reflector tube is longer than the light outlet of the reflector, so there is a distance between the light outlet of the outer inner reflector tube and the light outlet of the reflector; each reflector light inlet is connected to the LED bead, and the front of the light outlet of the reflector is the light outlet surface, with the optical axis located at the center of the light outlet surface and perpendicular to the light outlet surface; the light outlet surface is connected to the optical path of the projector engine, and can be directly connected to the light valve of LCD or DLP display; Its characteristics are: The staggered reflective cone array is composed of 4-30 reflective cone strips, which can be arranged into 2-15 pairs. The structure of the reflective cone strip includes a common panel and unit panels. The common panel is rectangular in shape, with two panels placed opposite each other and their long sides parallel. The unit panels are trapezoidal in shape, with 4-40 panels arranged into 2-20 pairs, and their base sides are parallel to each other. Two adjacent panels are placed opposite each other, forming a hollow, four-sided pyramid-shaped reflective cone, and the angle between the normals of the two opposite faces is between 3-20 degrees. The unit panels and the common panel are in a perpendicular planar position relationship. There are multiple reflective cones arranged in a row within the reflective cone strip. The reflective cone strip is formed by twisting and tightening the connecting protrusions of the common panel and unit panel with the through holes, or by direct bonding or welding. The components are arranged in a staggered manner, and the corresponding LED beads are also arranged in a staggered manner.

2. The offset reflector cone projector light source device according to claim 1, characterized in that: There are two options for the density of the reflective cones in reflective cone strips: one is a uniform linear distribution, and the other is a non-uniform nonlinear distribution. One type of nonlinear distribution is that the density is lowest in the central region of the reflective cone on the reflective cone strip, and the density increases towards both ends, showing a gradual trend. Another type of nonlinear distribution is the nonlinearity of the orientation angle of each reflector cone: the direction of the light emitted from the reflector cone in the central region is perpendicular to the light-emitting surface; while the direction of the light emitted from the reflector cone deviating from the central region is biased towards the central region of the light-emitting surface. In this case, the array spacing of the LED chips on the LED array PCB is also the spacing at the entrance of the reflector cone array, which is greater than the spacing at the exit of the reflector cone array.

3. The offset reflector cone projector light source device according to claim 1, characterized in that: A reflective cone is a hollow reflective or solid transparent medium; its shape includes a square pyramid, a multi-faceted pyramid, or a cone.

4. The offset reflector cone projector light source device according to claim 1, characterized in that: The unit panels of the reflective cone array can be independent flat panels or bent panels folded in pairs; or the reflective cone array can have multiple common panels; the ends of 2-20 common panels are connected to the whole panel, and then folded in pairs along each fold line to form the common panel connection of the reflective cone array.

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