CN110174813A - Light engine and projector - Google Patents

Abstract

The invention discloses an optical engine and a projector, wherein the optical engine comprises: an illumination unit; an imaging unit installed on the light output side of the illumination unit; a lens unit installed between the illumination unit and the imaging unit, and the lens unit has a facing The concentrating surface of the lighting unit, the optical surface facing the imaging unit, and the reflective surface located on the same side of the concentrating surface and the optical surface, the optical surface and the light emitted by the lighting unit are set at an angle; the polarization unit is installed on the lens unit and the imaging unit Between the units, the polarization unit has a polarization plane facing the imaging unit, and the polarization plane and the optical plane are set at an angle greater than 0°; and the LCOS chip is installed between the polarization unit and the imaging unit, and the LCOS chip reflects and passes through the polarization plane The light to the polarization plane, so that the light reflected by the LCOS chip is reflected to the imaging unit by the polarization plane. Such arrangement reduces the structural size of the optical engine, which is beneficial to reducing the volume of the projector.

Description

Optical Engine and Projector

technical field

The invention relates to the technical field of projection equipment, in particular to an optical engine and a projector.

Background technique

Existing projectors generally include a housing and an optical engine installed in the housing. The optical engine includes a light source, a condensing lens, a reflector, a dodging sheet, an imaging prism, an LCOS chip (Liquid Crystal on Silicon, liquid crystal attached silicon) and Lens, wherein the condenser lens is installed on the light emitting side of the light source, the light homogenizing sheet is installed on the light emitting side of the condenser lens, and the polarizer is installed on the light emitting side of the light uniform sheet, and the polarization plane of the polarizing sheet is in a 45-degree angle to the light Angle setting, the LCOS chip is installed on one side of the polarizer and is used to receive the light reflected by the polarizer, and the LCOS chip deflects the light so that the light reflected by the LCOS chip can pass through the polarizer and enter the lens. The lens is installed on the opposite side of the LCOS chip, and the image formed by the LCOS chip is transmitted to the lens through the polarizer.

However, each optical element of the optical engine in the existing projector is arranged in an L shape, which requires a large installation space for the optical engine of the projector, resulting in a relatively large overall volume of the projector.

Contents of the invention

The main purpose of the present invention is to provide an optical engine aimed at reducing the volume of the projector.

In order to achieve the above object, an optical engine proposed by the present invention is applied to a projector, and the optical engine includes:

lighting unit;

an imaging unit installed on the light emitting side of the lighting unit;

A lens unit installed between the lighting unit and the imaging unit, the lens unit has a light-gathering surface facing the lighting unit, an optical surface facing the imaging unit, and an optical surface between the light-gathering surface and the imaging unit. The reflective surface on the same side as the optical surface, the optical surface and the light emitted by the lighting unit are set at an included angle, which reflects the light passing through the light-gathering surface to the reflective surface and is transmitted and reflected by the reflective surface the light;

a polarizing unit installed between the lens unit and the imaging unit, the polarizing unit has a polarization plane facing the imaging unit, the polarization plane and the optical plane are set at an angle greater than 0°, It can reflect or transmit light; and

An LCOS chip installed between the polarization unit and the imaging unit, the LCOS chip reflects the light passing through the polarization plane to the polarization plane, so that the light reflected by the LCOS chip is captured by the polarization plane reflected to the imaging unit.

Optionally, the plane of polarization is set at an included angle of 45° to the light emitted by the lighting unit, and the plane of polarization is also set at an angle of 45° to the LCOS chip.

Optionally, the polarizing unit also has a light-transmitting surface facing the optical surface and arranged parallel to the polarization surface, and the distance between the light-transmitting surface and the optical surface is changed from that of the light-transmitting surface to One side is gradually increased toward the other side of the light-transmitting surface.

Optionally, the polarizing unit has a light-transmitting surface facing the optical surface and having an angle greater than 0° with the polarization surface, and the distance between the light-transmitting surface and the optical surface is from One side of the light-transmitting surface gradually increases toward the other side of the light-transmitting surface.

Optionally, the light-gathering surface is configured as a convex arc surface, which has a predetermined curvature, so that all the light passing through the light-gathering surface converges on the optical surface.

Optionally, the reflective surface is coated with a reflective material.

Optionally, the reflective surface and the optical surface are arranged at an angle so that all light reflected by the reflective surface passes through the optical surface.

The present invention also proposes a projector, which includes a casing and an optical engine installed in the casing, and the optical engine includes:

lighting unit;

an imaging unit installed on the light emitting side of the lighting unit;

A lens unit installed between the lighting unit and the imaging unit, the lens unit has a light-gathering surface facing the lighting unit, an optical surface facing the imaging unit, and an optical surface between the light-gathering surface and the imaging unit. The reflective surface on the same side as the optical surface, the optical surface and the light emitted by the lighting unit are set at an included angle, which reflects the light passing through the light-gathering surface to the reflective surface and is transmitted and reflected by the reflective surface the light;

a polarizing unit installed between the lens unit and the imaging unit, the polarizing unit has a polarization plane facing the imaging unit, the polarization plane and the optical plane are set at an angle greater than 0°, It can reflect or transmit light; and

An LCOS chip installed between the polarization unit and the imaging unit, the LCOS chip reflects the light passing through the polarization plane to the polarization plane, so that the light reflected by the LCOS chip is captured by the polarization plane reflected to the imaging unit.

The optical engine of the present invention uses a lens unit and an LCOS chip, so that the lighting unit, lens unit, polarization unit, LCOS chip and imaging unit in the optical engine are arranged in rows, compared with the use of LCOS chips in the existing optical engine. In terms of each optical element in the existing optical engine being in an L-shaped row, the installation space required by the optical engine of the present invention is smaller, which makes the volume of the projector using the optical engine smaller, thereby Therefore, the projector with the optical engine can be applied to various electronic devices (such as smart glasses, mobile phones, etc.).

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained according to the structures shown in these drawings without creative effort.

FIG. 1 is a schematic structural view of an embodiment of an optical engine of the present invention;

FIG. 2 is a schematic structural diagram of another embodiment of the optical engine of the present invention.

Explanation of reference numbers:

label name label name 100 optical engine 31 Concentrating surface 10 lighting unit 32 optical surface 20 imaging unit 33 Reflective surface 30 lens unit 41 plane of polarization 40 polarizing unit 42 Translucent surface 50 LCOS chip

The realization of the purpose of the present invention, functional characteristics and advantages will be further described with reference to the accompanying drawings in conjunction with the embodiments.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

It should be noted that the descriptions involving "first", "second" and so on in the present invention are only for the purpose of description, and should not be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In addition, the meaning of "and/or" appearing in the full text is: including three parallel plans, taking "A/B" as an example, including plan A, or plan B, or a plan that satisfies both A and B. In addition, The technical solutions of the various embodiments can be combined with each other, but it must be based on the realization of those skilled in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of such technical solutions does not exist. Not within the scope of protection required by the present invention.

The present invention proposes an optical engine to change the arrangement of optical elements in the existing optical engine, thereby reducing the volume of the optical engine. Please refer to FIG. 1 or FIG. 2, and FIG. 1 shows an implementation of the optical engine of the present invention Fig. 2 shows a schematic structural diagram of another embodiment of the optical engine of the present invention. The optical engine 100 includes an illumination unit 10, an imaging unit 20, a lens unit 30, a polarizing unit 40, and an LCOS chip 50; wherein, the imaging unit 20 is installed on the light output side of the illumination unit 10; the lens unit 30 is installed on the illumination unit 10 Between the lens unit 30 and the imaging unit 20, the lens unit 30 has a concentrating surface 31 facing the lighting unit 10, an optical surface 32 facing the imaging unit 20, and a reflective surface 33 on the same side of the concentrating surface 31 and the optical surface 32; The polarizing unit 40 is installed between the lens unit 30 and the imaging unit 20, the polarizing unit 40 has a polarizing plane 41 facing the imaging unit 20, and the polarizing plane 41 and the optical plane 32 are arranged at an angle greater than 0°; the LCOS chip 50 is installed between the polarizing unit 40 and the imaging unit 20 .

The first lighting unit 10 can only be formed by a lamp capable of emitting light, and the first lighting unit 10 can also be composed of a lamp capable of emitting light and other optical elements, for example, the first lighting unit 10 can be composed of a white LED lamp; The first lighting unit 10 is composed of a red LED lamp, a blue LED lamp, a green LED lamp and two filters, the green LED lamp is arranged towards the reflection unit 30, and the two filters are installed on the green LED lamp and the reflection unit 30 Between them, the two optical filters are set at an included angle with the light emitted by the green LED lamp, the blue LED lamp and the red LED lamp are installed on the side of the two optical filters away from the imaging unit 20, and the blue LED lamp is opposite to the two Among the filters, the filter adjacent to the green LED light is set, and the red LED light is set against the filter adjacent to the reflection unit 30 in the two optical filters, and the filter adjacent to the green LED light can transmit green light and reflect blue light. The filter of the reflection unit 30 transmits green light and blue light while reflecting red light, so that the light emitted by the three-color LED lamp can be converged to form high-brightness light.

The imaging unit 20 can only be formed by an imaging lens, and the imaging unit 20 can also be composed of an imaging lens and a lens. For example, the imaging unit 20 is only formed by a lens, which receives the light reflected by the polarization unit 40 and forms an image; Unit 20 is made up of imaging lens and lens, and this lens can be convex lens or refraction lens, and it is installed between polarizing unit 40 and imaging lens, and if this lens is convex lens, it is used for gathering the light reflected by this polarizing unit 40, with All the light reflected by the polarization unit 40 is transmitted to the imaging lens. If the lens is a dioptric lens, it is used to change the light reflected by the polarization unit 40, so that the position of the imaging lens can be changed through the dioptric lens.

There are many shapes of the lens unit 30, which can be triangular prisms, quasi-triangular prisms, polygons and other shapes, which are not specifically limited here. Preferably, the lens unit 30 is a triangular prism or Arranged like a triangular prism, the side surface of the lens unit 30 facing the lighting unit 10 forms a concentrating surface 31, and the transparent surface forms an optical surface 32 on the side surface of the imaging unit 20, and the lens unit 30 connects the concentrating surface 31 and the optical surface The side surface of 32 forms a reflective surface 33, and the concentrating surface 31 is used to collect the light emitted by the lighting unit 10, and the reflective surface 33 is used to reflect the light reflected by the optical surface 32, and the optical surface 32 is used to reflect 31 to the reflective surface 33, the optical surface 32 is also used to transmit the light reflected by the reflective surface 33.

It should be noted that, in order to make the light passing through the concentrating surface 31 undergo total reflection on the optical surface 32, it needs to comply with Snell's law, n ₁ sinθ ₁ =n ₂ sinθ ₂ , where n ₁ and n ₂ are two The refractive index of the medium, θ ₁ and θ ₂ are the angles between the incident light or refracted light and the interface, respectively, called the angle of incidence and the angle of refraction. The principle is as follows: if the incident angle θ ₁ is equal to a certain angle θ _c , the refracted light goes along the tangent line of the refracted interface, that is, the refraction angle is 90°, at this time sinθ ₂ = 1, then it can be deduced that sinθ _c = sinθ ₁ = n ₂ /n ₁ . However, if the incident angle θ ₁ is greater than this value θ _c , the sine of the incident angle sinθ ₁ >n ₂ /n ₁ will result in sinθ ₂ >1, which is meaningless in mathematics, so there is no refracted light at this time And there is only reflected light, so total reflection occurs. The angle between the optical surface 32 and the light passing through the light-transmitting surface 42 is set according to Snell's law, that is, the angle between the optical surface 32 and the light passing through the light-transmitting surface is determined by the refractive index n1 of the lens unit 30 and the refractive index _{n2 of} the air. The size of the included angle between 42.

In addition, it should also be noted that the polarization plane 41 and the optical surface 32 are set at an angle greater than 0°, that is to say, the polarization plane 41 is not parallel to the optical plane 32, so as to avoid passing through the optical surface 32. The light on the plane 32 is reflected on the polarization plane 41 , thereby reducing the amount of light transmitted through the polarization plane 41 .

The shape of this polarizing unit 40 has many kinds, and it can be plate shape (please refer to Fig. 1), wedge-shaped (please refer to Fig. 2) etc., not enumerate one by one here; This polarizing unit 40 can be made of glass plate and Polarizing film constitutes, and this glass plate is installed between lens unit 30 and imaging unit 20, and this polarizing film is coated on the surface of this glass plate facing imaging unit 20, to form polarizing plane 41; This polarizing unit 40 can also be made of lens and polarizing film, the lens is installed between the lens unit 30 and the imaging unit 20, the polarizing film is coated on the surface of the lens facing the imaging unit 20 to form a polarizing plane 41; the polarizing unit 40 can also be made of other light-transmitting The materials and the formation of the polarizing film are not listed one by one here.

The LCOS (Liquid Crystal on Silicon) chip is liquid crystal on silicon, which is a matrix liquid crystal display device based on reflection mode, which makes the light reflected by the polarizing unit 40 onto the LCOS chip 50 be reflected back by the LCOS chip 50, At the same time, the LCOS chip 50 also polarizes the light, so that the light passing through the polarization plane 41 of the polarization unit 40 can be reflected to the imaging unit 20 through the polarization plane 41 of the polarization unit 40 .

When the optical engine 100 is in operation, the light emitted by the lighting unit 10 is collected on the optical surface 32 of the lens unit 30 through the light collecting surface 31 of the lens unit 30 and is totally reflected on the optical surface 32 of the lens unit 30, and the light is reflected to the reflector. After the reflection of the reflection surface 33 on the surface 33, it propagates to the optical surface 32 again, because when the light is reflected by the reflection surface 33 and propagates to the optical surface 32, the angle between the light and the optical surface 32 changes, which makes the reflection The light reflected by the surface 33 can be refracted at the optical surface 32, so that the light can pass through the optical surface 32 and propagate to the polarization plane 41 of the polarization unit 40, and the polarization plane 41 of the polarization unit 40 can be used for the light passing through the optical surface 32. The light passes through, and the LCOS chip 50 receives the light passing through the polarization plane 41 of the polarizing lens and reflects the light on the polarization plane 41 of the polarizing lens after polarization. The light of the polarization plane 41 of 40 cannot pass through the polarization plane 41, so that all the light reflected by the LCOS chip 50 is reflected by the polarization plane 41 of the polarizing lens to the imaging unit 20 to form a corresponding image.

The optical engine 100 of the present invention uses the lens unit 30 and the LCOS chip 50, so that the illumination unit 10, the lens unit 30, the polarization unit 40, the LCOS chip 50 and the imaging unit 20 in the optical engine 100 are arranged in a row, compared with the existing In terms of using LCOS chips in the optical engine 100 so that each optical element in the existing optical engine 100 is in an L-shaped row, the installation space required by the optical engine 100 in the present invention is smaller, which makes the application of the optical engine The volume of the projector 100 can be made smaller, so that the projector applied with the optical engine 100 can be applied to various electronic devices (such as smart glasses, mobile phones, etc.).

In order to reduce the installation space required by the optical engine 100, in one embodiment of the present invention, please refer to FIG. 1 or FIG. The polarization plane 41 is also set at an angle of 45° with the LCOS chip 50 . It is set so that the lighting unit 10, the polarizing unit 40 and the imaging unit 20 are located on the same straight line, and the extension direction of the LCOS chip 50 is parallel to the straight line where the lighting unit 10, the polarizing unit 40 and the imaging unit 20 are located, so that the optical The optical components of the engine 100 are arranged in a straight line as a whole, which further reduces the installation space required by the optical engine 100 .

It is worth noting that the light passing through the polarization plane 41 of the polarization unit 40 propagates vertically to the LCOS chip 50, and to make the light passing through the polarization plane 41 of the polarization unit 40 vertically propagate to the LCOS chip 50, it is necessary to adjust the light passing through the optical surface. The angle between the light at 32 and the plane of polarization 41, there are many ways to adjust the angle between the light passing through the optical plane 32 and the plane of polarization 41. In an embodiment of the present invention, please refer to FIG. 1, the polarization unit 40 It also has a light-transmitting surface 42 facing the optical surface 32 and parallel to the polarizing surface 41, the distance between the light-transmitting surface 42 and the polarizing surface 41 gradually increases from one end of the light-transmitting surface 42 to the other end thereof, That is, the gap between the light-transmitting surface 42 and the polarizing surface 41 is wedge-shaped. Such setting can make the angle between the light passing through the optical surface 32 and the light-transmitting surface 42 and the polarization plane 41 meet the preset requirement, so as to ensure that the light passing through the optical surface 32 can propagate vertically to the LCOS chip 50 .

Obviously, the angle between the light passing through the optical surface 32 and the polarization plane 41 can also be adjusted in other ways. In another embodiment of the present invention, please refer to FIG. 32 and the light-transmitting surface 42 set at an angle greater than 0° with the polarization plane 41, the distance between the light-transmission surface 42 and the polarization plane 41 gradually increases from one end to the other end of the light-transmission surface 42. Such setting makes the light passing through the optical surface 32 undergo the first refraction on the transmission surface, and the second refraction occurs when passing through the polarizing surface 41, thus ensuring that the light can be refracted along the vertical direction of the LCOS chip after being refracted twice. The direction of 50 is propagated to the LCOS chip 50 .

In order to make most or even all of the light emitted by the lighting unit 10 converge on the optical surface 32, in an embodiment of the present invention, please refer to FIG. 1 or FIG. It has a predetermined curvature, which makes the concentrating surface 31 have the effect of a convex lens, and the light emitted by the lighting unit 10 can be fully converged on the optical surface 32 under the action of the concentrating surface 31, thus improving the utilization of light rate, and at the same time, the imaging effect of the optical engine 100 can be guaranteed.

In order to enable the reflective surface 33 to reflect all the light to the optical surface 32, in an embodiment of the present invention, the reflective surface 33 is convexly provided with a reflective material (not shown), and the reflective material can be metal aluminum, metal silver or other dielectric films. With such arrangement, all the light reflected from the optical surface 32 to the reflective surface 33 can be reflected back to the optical surface 32 , thus avoiding the problem of part of the light passing through the reflective surface 33 and improving the utilization rate of light.

Of course, in order to improve the reflection effect of the reflective surface 33, it can also be realized by adjusting the angle between the reflective surface 33 and the optical surface 32, so that the light reflected by the optical surface 32 can be completely reflected back to the optical surface 32 by the reflective surface 33, and also That is to say, the light reflected by the optical surface 32 is totally reflected at the reflective surface 33 , so that all the light propagating to the reflective surface 33 can be reflected back to the optical surface 32 .

It should be noted that the size of the included angle between the reflective surface 33 and the optical surface 32 is also related to the size of the included angle between the reflective surface 33 and the optically reflected light. To reflect total reflection of the light, Snell's law is required, that is, n ₁ sinθ ₁ = n ₂ sinθ ₂ , where n ₁ and n ₂ are the refractive indices of the two media, and θ ₁ and θ ₂ are the incident light or The angle between the refracted light and the interface is called the angle of incidence and the angle of refraction. The principle is as follows: if the incident angle θ ₁ is equal to a certain angle θ _c , the refracted light goes along the tangent line of the refracted interface, that is, the refraction angle is 90°, at this time sinθ ₂ = 1, then it can be deduced that sinθ _c = sinθ ₁ = n ₂ /n ₁ . However, if the incident angle θ ₁ is greater than this value θ _c , the sine of the incident angle sinθ ₁ >n ₂ /n ₁ will result in sinθ ₂ >1, which is meaningless in mathematics, so there is no refracted light at this time And there is only reflected light, so total reflection occurs. The angle between the reflective surface 33 and the light reflected by the optical surface 32 is set according to Snell's law, that is, the angle between the optical surface 32 and the light passing through the light-transmitting surface is determined by the refractive index n1 of the lens unit 30 and the refractive index _{n2 of} the air. The size of the included angle between 42.

In addition, it should be noted that the reflective surface 33 may be a plane, the reflective surface 33 may also be a curved surface, and the reflective surface 33 may also be partly planar and partly curved, which is not specifically limited here.

The present invention proposes a projector, which includes a casing and an optical engine 100 installed in the casing. For the specific structure of the optical engine 100, refer to the above-mentioned embodiments, since this projector adopts all the technical solutions of all the above-mentioned embodiments , so at least it has all the beneficial effects brought by the technical solutions of the above embodiments, and will not be repeated here.

The above is only a preferred embodiment of the present invention, and does not therefore limit the patent scope of the present invention. Under the inventive concept of the present invention, the equivalent structural transformation made by using the description of the present invention and the contents of the accompanying drawings, or direct/indirect use All other relevant technical fields are included in the patent protection scope of the present invention.

Claims (8)

1. A kind of optical engine, is applied to projector, is characterized in that, described optical engine comprises: lighting unit; an imaging unit installed on the light emitting side of the lighting unit; A lens unit installed between the lighting unit and the imaging unit, the lens unit has a light-gathering surface facing the lighting unit, an optical surface facing the imaging unit, and an optical surface between the light-gathering surface and the imaging unit. The reflective surface on the same side as the optical surface, the optical surface and the light emitted by the lighting unit are set at an included angle, which reflects the light passing through the light-gathering surface to the reflective surface and is transmitted and reflected by the reflective surface the light; a polarizing unit installed between the lens unit and the imaging unit, the polarizing unit has a polarization plane facing the imaging unit, the polarization plane and the optical plane are set at an angle greater than 0°, It can reflect or transmit light; and An LCOS chip installed between the polarization unit and the imaging unit, the LCOS chip reflects the light passing through the polarization plane to the polarization plane, so that the light reflected by the LCOS chip is captured by the polarization plane reflected to the imaging unit. 2. The optical engine according to claim 1, wherein the plane of polarization is set at an angle of 45° to the light emitted by the lighting unit, and the plane of polarization is also at an angle of 45° to the LCOS chip set up. 3. The optical engine according to claim 1, wherein the polarizing unit also has a light-transmitting surface facing the optical surface and parallel to the polarization plane, the light-transmitting surface and the optical The distance between the surfaces is gradually increased from one side of the light-transmitting surface to the other side of the light-transmitting surface. 4. The optical engine according to claim 1, wherein the polarizing unit has a light-transmitting surface facing the optical surface and having an angle greater than 0° with the polarization surface, and the transmitting surface The distance between the light surface and the optical surface gradually increases from one side of the light transmission surface to the other side of the light transmission surface. 5. The optical engine according to claim 1, wherein the light-gathering surface is configured as a convex arc surface with a predetermined curvature, so that all the light passing through the light-gathering surface converges on the optical engine. noodle. 6. The optical engine according to claim 1, wherein the reflective surface is coated with a reflective material. 7 . The optical engine according to claim 1 , wherein the reflective surface is arranged at an angle with the optical surface so that all light reflected by the reflective surface passes through the optical surface. 8 . 8. A projector, characterized by comprising a casing and the optical engine according to any one of claims 1 to 7, the optical engine being installed in the casing.