阅读说明：本技术 投影光机 (Projection light machine ) 是由 彭旭 韩欣欣 于 2021-08-30 设计创作，主要内容包括：本发明提供一种投影光机,包括光源、反射式偏振片、成像透镜组、第一反射件和第二反射件,光源用于发射出自然光或圆偏振光至反射式偏振片,第一线偏振光经反射式偏振片反射后投射至成像透镜组,第二线偏振光透射过反射式偏振片；第一反射件用于将从反射式偏振片透射过的第二线偏振光调节偏振方向后形成第三线偏振光,第三线偏振光经反射式偏振片反射至第二反射件,第二反射件用于将反射式偏振片反射的第三线偏振光调节偏振方向后形成第四线偏振光；其中,第一线偏振光的偏振方向与第四线偏振光的偏振方向相同,第一线偏振光与第四线偏振光形成有预设夹角。该投影光机具有能够获得更高分辨率和更清晰的图像的优点。(The invention provides a projection optical machine, which comprises a light source, a reflective polaroid, an imaging lens group, a first reflecting piece and a second reflecting piece, wherein the light source is used for emitting natural light or circularly polarized light to the reflective polaroid; the first reflecting piece is used for adjusting the polarization direction of the second linear polarized light transmitted by the reflecting type polaroid to form third linear polarized light, the third linear polarized light is reflected to the second reflecting piece through the reflecting type polaroid, and the second reflecting piece is used for adjusting the polarization direction of the third linear polarized light reflected by the reflecting type polaroid to form fourth linear polarized light; the polarization direction of the first linearly polarized light is the same as that of the fourth linearly polarized light, and a preset included angle is formed between the first linearly polarized light and the fourth linearly polarized light. The projection light machine has the advantages of being capable of obtaining higher resolution and clearer images.)

1. A projection light engine, comprising:

the device comprises a light source, a reflective polarizing film and an imaging lens group, wherein the light source is used for emitting natural light or circularly polarized light to the reflective polarizing film, the reflective polarizing film is used for reflecting first linearly polarized light in a first polarization direction and transmitting second linearly polarized light in a second polarization direction, the first polarization direction is perpendicular to the second polarization direction, the first linearly polarized light is reflected by the reflective polarizing film and then projected to the imaging lens group, and the second linearly polarized light is transmitted through the reflective polarizing film;

the first reflecting piece is used for adjusting the polarization direction of second linear polarized light transmitted by the reflecting type polaroid to form third linear polarized light, the third linear polarized light is reflected to the second reflecting piece through the reflecting type polaroid, the second reflecting piece is used for adjusting the polarization direction of the third linear polarized light reflected by the reflecting type polaroid to form fourth linear polarized light, and the fourth linear polarized light penetrates through the reflecting type polaroid and then is projected to the imaging lens group; the polarization direction of the first linearly polarized light is the same as that of the fourth linearly polarized light, and a preset included angle is formed between the first linearly polarized light and the fourth linearly polarized light.

2. The projection light engine of claim 1, wherein the first reflecting member comprises a first wave plate and a first reflecting plate, the first wave plate is arranged facing the reflective polarizer, and the second linearly polarized light transmitted by the reflective polarizer passes through the first wave plate, the first reflecting plate and the first wave plate in sequence to form the third linearly polarized light; the second reflection piece comprises a second wave plate and a second reflection plate, the second wave plate faces the reflection type polaroid, and third linearly polarized light reflected by the reflection type polaroid sequentially passes through the second wave plate, the second reflection plate and the second wave plate to form fourth linearly polarized light.

3. The light projector of claim 2, wherein the first reflector and the second reflector are mirrors or polarizers.

4. The light engine of claim 2, wherein the first and second wave plates are half-wave plates or both the first and second wave plates are made of two quarter-wave plates.

5. The projection light machine of claim 1, wherein the polarization direction of the second linearly polarized light is different from the polarization direction of the third linearly polarized light by 90 degrees, the polarization direction of the third linearly polarized light is different from the polarization direction of the fourth linearly polarized light by 90 degrees, and the polarization direction of the first linearly polarized light is the same as the polarization direction of the fourth linearly polarized light.

6. The light projector as defined in claim 1, wherein the light source comprises a microdisplay, the microdisplay and the first reflector are disposed on opposite sides of the reflective polarizer, and the second reflector and the imaging lens group are disposed on opposite sides of the reflective polarizer.

7. The light projector as claimed in claim 6, wherein the reflective polarizer is at an angle of 45 degrees to the microdisplay, the first reflector is parallel to the microdisplay, and the second reflector is at an angle of (90 ± Δ) degrees to the microdisplay, where 0 < Δ < 2.5.

8. The light projector as claimed in claim 6 wherein the reflective polarizer is at an angle of (45 ± α) degrees to the microdisplay, the first reflector is parallel to the microdisplay, and the second reflector is at an angle of 90 degrees to the microdisplay, where 0 < α < 5.

9. The light projector of claim 6 wherein the reflective polarizer is angled 45 degrees from the microdisplay, the first reflector is angled ± β degrees from the microdisplay, and the second reflector is angled 90 degrees from the microdisplay, wherein 0 < β < 5.

10. The light engine of claim 1, wherein the predetermined angle is 0 ° < predetermined angle < 5 °.

Technical Field

The invention relates to the technical field of optical machines, in particular to a projection optical machine.

Background

An optical machine, also called an optical engine, can image light emitted by a micro display at a certain spatial position, and is widely applied to the field of projection display. With the improvement of the sensory pursuit, the requirements of people on high resolution and high definition of images are higher and higher. For the optical machine, the resolution of the image formed by the optical machine is related to the resolution of the light source (microdisplay), and since the pixel points on the microdisplay do not participate in imaging, the image resolution of the optical machine is usually smaller than the pixel resolution of the microdisplay, so that the image resolution is low, and the customer demand cannot be met.

Therefore, there is a need for a new optical projection engine to solve or at least alleviate the above technical drawbacks.

Disclosure of Invention

The invention mainly aims to provide a projection light machine, and aims to solve the technical problem that the image resolution of the projection light machine is low in the prior art.

To achieve the above object, the present invention provides a projection optical machine comprising:

the device comprises a light source, a reflective polarizing film and an imaging lens group, wherein the light source is used for emitting natural light or circularly polarized light to the reflective polarizing film, the reflective polarizing film is used for reflecting first linearly polarized light in a first polarization direction and transmitting second linearly polarized light in a second polarization direction, the first polarization direction is perpendicular to the second polarization direction, the first linearly polarized light is reflected by the reflective polarizing film and then projected to the imaging lens group, and the second linearly polarized light is transmitted through the reflective polarizing film;

the first reflecting piece is used for adjusting the polarization direction of second linear polarized light transmitted by the reflecting type polaroid to form third linear polarized light, the third linear polarized light is reflected to the second reflecting piece through the reflecting type polaroid, the second reflecting piece is used for adjusting the polarization direction of the third linear polarized light reflected by the reflecting type polaroid to form fourth linear polarized light, and the fourth linear polarized light penetrates through the reflecting type polaroid and then is projected to the imaging lens group; the polarization direction of the first linearly polarized light is the same as that of the fourth linearly polarized light, and a preset included angle is formed between the first linearly polarized light and the fourth linearly polarized light.

Optionally, the first reflecting member includes a first wave plate and a first reflecting plate, the first wave plate is disposed facing the reflective polarizing plate, and the second linearly polarized light transmitted by the reflective polarizing plate sequentially passes through the first wave plate, the first reflecting plate and the first wave plate to form the third linearly polarized light; the second reflection piece comprises a second wave plate and a second reflection plate, the second wave plate faces the reflection type polaroid, and third linearly polarized light reflected by the reflection type polaroid sequentially passes through the second wave plate, the second reflection plate and the second wave plate to form fourth linearly polarized light.

Optionally, the first reflective sheet and the second reflective sheet are mirrors or polarizers.

Optionally, the first wave plate and the second wave plate are both half-wave plates, or both the first wave plate and the second wave plate are made of two quarter-wave plates.

Optionally, the polarization direction of the second linearly polarized light is different from the polarization direction of the third linearly polarized light by 90 degrees, the polarization direction of the third linearly polarized light is different from the polarization direction of the fourth linearly polarized light by 90 degrees, and the polarization direction of the first linearly polarized light is the same as the polarization direction of the fourth linearly polarized light.

Optionally, the light source includes a micro-display, the micro-display and the first reflecting element are disposed on two opposite sides of the reflective polarizer, and the second reflecting element and the imaging lens group are disposed on the other opposite sides of the reflective polarizer.

Optionally, an included angle between the reflective polarizer and the microdisplay is 45 degrees, the first reflecting element is arranged in parallel with the microdisplay, and an included angle between the second reflecting element and the microdisplay is (90 ± Δ), where Δ is greater than 0 and less than 2.5.

Optionally, an included angle between the reflective polarizer and the microdisplay is (45 ± α), the first reflecting element is disposed in parallel with the microdisplay, and an included angle between the second reflecting element and the microdisplay is 90 degrees, where α is greater than 0 and less than 5.

Optionally, an included angle between the reflective polarizer and the microdisplay is 45 degrees, an included angle between the first reflecting element and the microdisplay is ± β degrees, and an included angle between the second reflecting element and the microdisplay is 90 degrees, where β is greater than 0 and less than 5.

Optionally, the preset included angle is greater than 0 ° and less than 5 °.

In the technical scheme of the invention, light emitted by a light source is equally divided into two parts of first linearly polarized light and second linearly polarized light with the same energy through a reflective polarizing film, the first linearly polarized light is reflected to an imaging lens group through the reflective polarizing film, the second linearly polarized light is transmitted through the reflective polarizing film and then passes through the adjusting action of a first reflecting piece and a second reflecting piece to form fourth linearly polarized light with the same polarization direction as the first linearly polarized light, the fourth linearly polarized light is also projected to the imaging lens group, a tiny preset included angle is formed between the first linearly polarized light and the fourth linearly polarized light, the light equivalent to the same pixel point is equally divided into two beams of light with smaller included angle and projected to an imaging surface, the included angles of the two beams of light emitted by different pixel points after light splitting are the same, so that a tiny displacement exists between two images after imaging, finally, the two images are mutually superposed, so that the resolution of the image sent by the optical machine is doubled. The method has the advantages of being capable of obtaining higher resolution and clearer images, simple in manufacturing process and very suitable for mass production.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

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

FIG. 2 is a schematic diagram of the light paths of two light beams A and B of the projection optical machine according to the embodiment of the present invention;

fig. 3 is a schematic diagram of overlapping the first linearly polarized light image and the fourth linearly polarized light image according to the embodiment of the invention. The reference numbers illustrate:

1. a microdisplay; 2. a reflective polarizer; 3. a first reflective member; 31. a first wave plate; 32. a first reflective sheet; 4. a second reflector; 41. a second wave plate; 42. a second reflective sheet; 5. an imaging lens group; 6. a quarter-wave plate.

The implementation, functional features and advantages of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent 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 obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It should be noted that all the directional indicators (such as the upper and lower … …) in the embodiment of the present invention are only used to explain the relative position relationship, movement, etc. of the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are only for descriptive purposes and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

Moreover, the technical solutions in the embodiments of the present invention may be combined with each other, but it is necessary to be able to be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent, and is not within the protection scope of the present invention.

Referring to fig. 1 to 3, fig. 1 shows only a light path traveling pattern of a single light ray a in a projection light engine, fig. 2 shows light path traveling patterns of a light ray a and a light ray B in the projection light engine, a first linearly polarized light is denoted by L1 in fig. 1 and 2, a second linearly polarized light is denoted by L2 in fig. 1 and 2, a third linearly polarized light is denoted by L3 in fig. 1 and 2, and a fourth linearly polarized light is denoted by L4 in fig. 1 and 2, the present invention provides a projection light engine comprising:

the device comprises a light source, a reflective polarizing film 2 and an imaging lens group 5, wherein the light source is used for emitting natural light or circularly polarized light to the reflective polarizing film 2, the reflective polarizing film 2 is used for reflecting first linearly polarized light in a first polarization direction and transmitting second linearly polarized light in a second polarization direction, the first polarization direction is vertical to the second polarization direction, the first linearly polarized light is reflected by the reflective polarizing film 2 and then is projected to the imaging lens group 5, and the second linearly polarized light is transmitted through the reflective polarizing film 2;

the first reflecting piece 3 is used for adjusting the polarization direction of second linear polarized light transmitted by the reflecting type polarizing plate 2 to form third linear polarized light, the third linear polarized light is reflected to the second reflecting piece 4 through the reflecting type polarizing plate 2, the second reflecting piece 4 is used for adjusting the polarization direction of the third linear polarized light reflected by the reflecting type polarizing plate 2 to form fourth linear polarized light, and the fourth linear polarized light is projected to the imaging lens group 5 after penetrating through the reflecting type polarizing plate 2; the polarization direction of the first linearly polarized light is the same as that of the fourth linearly polarized light, and a preset included angle is formed between the first linearly polarized light and the fourth linearly polarized light.

Resolution is also called resolution and resolution. Generally, the higher the resolution of an image, the more pixels are included, and the sharper the image, so that high resolution is an important prerequisite for ensuring the sharpness of a color display. The resolution can be expressed as the number of pixels in each direction. For an optical machine, the resolution of the resulting image is related to the resolution of the microdisplay 1. Because the pixel points on the micro display 1 do not participate in imaging, the image resolution of the optical machine is smaller than the pixel resolution of the micro display 1 under normal conditions, and the image resolution of the optical machine is difficult to improve.

In the embodiment, light emitted by a light source is equally divided into two parts of first linearly polarized light and second linearly polarized light with the same energy through the reflective polarizing film 2, the first linearly polarized light is reflected to the imaging lens group 5 through the reflective polarizing film 2, the second linearly polarized light is transmitted through the reflective polarizing film 2 and then passes through the adjusting action of the first reflecting piece 3 and the second reflecting piece 4 to form fourth linearly polarized light with the same polarization direction as the first linearly polarized light, the fourth linearly polarized light is projected to the imaging lens group 5, and a micro preset included angle is formed between the first linearly polarized light and the fourth linearly polarized light. Like this, the light that is equivalent to same pixel is equallyd divide into two bundles of light that the contained angle is less and is thrown to the imaging surface, and two bundles of light contained angles after the light that different pixel sent is split are the same for there is a small displacement (if can be that all pixels shift a pixel size, when the displacement is less, people's eye looks complete overlapping) between two images after the formation of image, and two final images superpose each other, make the image resolution ratio that the ray apparatus sent double. Specifically, referring to fig. 3, an image a in fig. 3 is an image formed by the first linearly polarized light in fig. 1, and an image b in fig. 3 is an image formed by the fourth linearly polarized light in fig. 1, because the two have a slight displacement, an image s formed after the superposition is doubled in the pixel of the superposition portion, so that the resolution is higher, and the image is clearer. The embodiment has the advantages of being capable of obtaining higher resolution and clearer images, simple in manufacturing process and very suitable for mass production.

In one embodiment, the preset included angle refers to an included angle between the first linearly polarized light and the fourth linearly polarized light, and the size of the preset included angle is greater than 0 degrees and less than 5 degrees. When the preset included angle is smaller, the displacement of the image is smaller, the human eyes cannot distinguish the small difference of the image, and the pixels of the overlapped part of the two images are doubled, so that the resolution of the overlapped image is high, and the image is clear. However, when the included angle between the first linearly polarized light and the fourth linearly polarized light is larger than the preset included angle, the displacement of the image is large, and human eyes look like two images, so that the human eyes feel double images, and the images are unclear. Therefore, a range is set for the preset angle, and specifically, the preset angle range may be set to 0 ° < the preset angle < 5 °.

In an embodiment, the first reflecting member 3 includes a first wave plate 31 and a first reflecting plate 32, the first wave plate 31 is disposed facing the reflective polarizer 2, and the second linearly polarized light transmitted by the reflective polarizer 2 sequentially passes through the first wave plate 31, the first reflecting plate 32, and the first wave plate 31 to form a third linearly polarized light; the second reflecting member 4 includes a second wave plate 41 and a second reflecting plate 42, the second wave plate 41 is disposed facing the reflective polarizer 2, and the third linearly polarized light reflected from the reflective polarizer 2 sequentially passes through the second wave plate 41, the second reflecting plate 42, and the second wave plate 41 to form a fourth linearly polarized light. The second linearly polarized light is emitted to the first reflection plate 32 after the polarization direction is adjusted by the first wave plate 31, and is reflected by the first reflection plate 32, and is emitted to the reflective polarizer 2 after the polarization direction is adjusted by the first wave plate 31 again. Specifically, the polarization direction of the second linearly polarized light and the polarization direction of the third linearly polarized light may differ by 90 degrees, that is, the polarization direction of the second linearly polarized light is perpendicular to the polarization direction of the third linearly polarized light, so that the third linearly polarized light can be completely reflected to the second reflection member 4 by the reflection-type polarizing plate 2, the third linearly polarized light is emitted to the second reflection plate 42 after the polarization direction of the third linearly polarized light is adjusted by the second wave plate 41, and is reflected by the second reflection plate 42, and the polarization direction of the third linearly polarized light is adjusted by the second wave plate 41 again to form the fourth linearly polarized light to be emitted to the reflection-type polarizing plate 2, specifically, the polarization direction of the third linearly polarized light and the polarization direction of the fourth linearly polarized light differ by 90 degrees, that is, the polarization direction of the third linearly polarized light is perpendicular to the polarization direction of the fourth linearly polarized light, so that the fourth linearly polarized light can completely transmit through the reflection-type polarizing plate 2 to the imaging lens group 5, and the polarization direction is adjusted twice by the first reflecting piece 3 and the second reflecting piece 4, so that the polarization direction of the fourth linearly polarized light is the same as that of the first linearly polarized light, and the images of the fourth linearly polarized light and the first linearly polarized light are favorably superposed to form an image with doubled resolution.

In one embodiment, the first and second reflective sheets 32 and 42 are mirrors or polarizers. The first reflection plate 32 and the second reflection plate 42 mainly function to reflect light, and are used to reflect light incident from the first wave plate 31 or the second wave plate 41 to the first wave plate 31 or the second wave plate 41 again. Now, the arrangement angles of the reflection plates and the wave plate will be described by taking the first reflection plate 32 as the first polarizing plate and the second reflection plate 42 as the second polarizing plate as an example. Referring to fig. 1, for convenience of description, a three-dimensional coordinate system of xyz is shown in fig. 1, in an embodiment, an included angle between an orthogonal projection of a polarization transmission axis of the reflective polarizer 2 on a plane xoz and an x-axis is 0 °, an included angle between an orthogonal projection of a polarization reflection axis of the first polarizer on a plane xoz and the x-axis is 45 °, and an included angle between an orthogonal projection of a fast axis (or a slow axis) of the first polarizer on a plane xoz and the x-axis is 45 °, so that a polarization direction of the second linearly polarized light is changed by 45 ° when the second linearly polarized light passes through the first wave plate 31 for the first time, and then the polarization direction of the second linearly polarized light is changed by 45 ° when the second linearly polarized light passes through the first wave plate 31 for the second time after the second linearly polarized light passes through the first reflecting member 3, thereby forming a third linearly polarized light. Similarly, the included angle between the orthographic projection of the polarized light transmission axis of the second polarizer on the yoz plane and the y axis is 45 °, and the orthographic projection of the fast axis (or the slow axis) of the second wave plate 41 on the yoz plane and the y axis is 45 °, so that the linearly polarized light of the third polarized light passes through the second reflector 4 and then is changed by 90 ° to form fourth linearly polarized light.

In one embodiment, the first wave plate 31 and the second wave plate 41 are both half-wave plates, or the first wave plate 31 and the second wave plate 41 are both made of two quarter-wave plates 6. The polarization direction of linearly polarized light can be changed by adopting the half-wave plate without changing the polarization state of the linearly polarized light. Of course, it is also possible to use two quarter-wave plates 6 which function as half-wave plates in a stack.

In one embodiment, the light source comprises microdisplay 1, microdisplay 1 and first reflector 3 are disposed on opposite sides of reflective polarizer 2, and second reflector 4 and imaging lens group 5 are disposed on opposite sides of reflective polarizer 2. Specifically, referring to fig. 1 or fig. 2, the microdisplay 1, the first reflecting member 3, the second reflecting member 4 and the imaging lens group 5 form four sides of a square frame, the reflective polarizer 2 is enclosed, and the imaging lens group 5 is used for imaging light emitted from the microdisplay 1. In addition, when the micro display 1 emits natural light or circularly polarized light, the micro display 1 can be directly adopted; when the micro display 1 emits linearly polarized light, a layer of quarter-wave plate 6 can be added on the micro display 1, and the included angle between the polarization direction of the linearly polarized light and the fast and slow axes of the quarter-wave plate 6 is 45 degrees, so that the light after passing through the quarter-wave plate 6 becomes circularly polarized light.

In order to obtain the first linearly polarized light and the fourth linearly polarized light having the preset included angle, the first reflecting member 3 or the second reflecting member 4 or the reflective polarizer 2 may be controlled to deviate from the normal state by a preset angle. Such as:

in one embodiment, the reflective polarizer 2 is at an angle of 45 degrees to the microdisplay 1, the first reflector 3 is parallel to the microdisplay 1, and the second reflector 4 is at an angle of (90 ± Δ) degrees to the microdisplay 1. Because, if the included angle between the second reflecting member 4 and the micro display 1 is set to be 90 degrees conventionally, the fourth linearly polarized light formed after the third linearly polarized light incident to the second reflecting member 4 passes through the second reflecting member 4 will return reversely along the original optical path, and then the fourth linearly polarized light will completely coincide with the first linearly polarized light (the included angle is 0 degree) after passing through the reflective polarizer 2, and the function of doubling the resolution cannot be achieved. Therefore, the included angle between the second reflecting element 4 and the microdisplay 1 needs to be adjusted to deviate from the normal setting by a first preset angle Δ, and of course, the value of the first preset angle is not too large, otherwise, the two images cannot be clearly superimposed, and specifically, the first preset angle may be set to 0 < Δ < 2.5.

In another embodiment the reflective polarizer 2 is angled (45 ± α) degrees to the microdisplay 1, the first reflecting element 3 is arranged parallel to the microdisplay 1, and the second reflecting element 4 is angled 90 degrees to the microdisplay 1, where 0 < α < 5. In yet another embodiment the reflective polarizer 2 is angled 45 degrees to the microdisplay 1, the first reflecting element 3 is angled ± β degrees to the microdisplay 1, and the second reflecting element 4 is angled 90 degrees to the microdisplay 1, where 0 < β < 5. The principle that the reflective polarizer 2 deviates from the normal state by alpha and the first reflector 3 deviates from the normal state by beta is similar to that described above, and the included angle is formed between the first linearly polarized light and the fourth linearly polarized light, so that the two images can be overlapped, the resolution of the images is improved, and meanwhile, the situation that the images are not clear due to the fact that the preset included angle is too large is prevented through limitation of the range, and the repeated description is omitted here.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents made by the claims and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.