CN112180669A

CN112180669A - Projection device

Info

Publication number: CN112180669A
Application number: CN201910592161.7A
Authority: CN
Inventors: 王志煌
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-07-03
Filing date: 2019-07-03
Publication date: 2021-01-05

Abstract

A projection device comprises a relay optical system and a reflective optical system arranged along an optical axis; the reflective optical system comprises a reflective element and at least one lens; the at least one lens is located between the reflective element and the relay optical system and has a first optical surface and a second optical surface opposite to each other, and the second optical surface faces the relay optical system; wherein, after the image light beam passes through the relay optical system, the image light beam is incident on the at least one lens from the second optical surface, and is incident on a reflective surface of the reflective element from the first optical surface, and after being reflected by the reflective surface, passes through the at least one lens, and then leaves the at least one lens from the second optical surface, and is projected in the direction of the imaging surface, and the effective diameters of the reflective element and the at least one lens are both located on the same side of the optical axis.

Description

Projection device

Technical Field

The present invention relates to projection devices; in particular to a projection device.

Background

With the progress of video technology, projection apparatuses suitable for general home space and work meetings are becoming more popular, and the projection lens for clearly displaying images on the screen is an important core element of the projection apparatus.

With the progress of the technology, in order to meet the limitation of the use space, manufacturers further manufacture short-focus projection equipment, so that the short-focus projection equipment can achieve the effect of clear projection in the limited space. However, the short-focus projection apparatus usually uses a large number of lenses to achieve short focus and have high optical performance, but the large number of lenses causes the problem that the weight and volume of the short-focus projection lens cannot be reduced, and thus cannot meet the portable and light-weight requirements desired by people.

Therefore, the short-focus projection lens has high optical performance, and the size and weight of the short-focus projection lens are required to be reduced, so that the short-focus projection device formed by the short-focus projection lens meets the requirements of light weight and portability expected by the public.

Disclosure of Invention

In view of the above, the present invention provides a projection apparatus, which can effectively reduce the size and has high optical performance.

The projection device includes a relay optical system and a reflection optical system arranged along an optical axis, the relay optical system is used for receiving the image beam and allowing the image beam to pass through, the reflection optical system includes a reflection element and at least one lens, and the at least one lens is located between the reflection element and the relay optical system and has a first optical surface and a second optical surface opposite to each other, and the second optical surface faces the relay optical system

Wherein, after the image beam passes through the relay optical system, the image beam enters the at least one lens from the second optical surface, enters a reflection surface of the reflection element from the first optical surface, passes through the at least one lens after being reflected by the reflection surface, leaves the at least one lens from the second optical surface, and projects towards the direction of the imaging surface

Wherein, in a direction parallel to the optical axis, a minimum distance between the reflecting element and the at least one lens is smaller than a minimum distance between the at least one lens and the relay optical system, and the minimum distance between the reflecting element and the at least one lens is greater than or equal to 0;

wherein, an extending surface of the optical axis is divided into a first portion and a second portion, the image beam is incident into the reflective optical system from the first portion, and the image beam is projected toward the imaging surface from the second portion after leaving the at least one lens from the second optical surface; in addition, the effective diameter of the relay optical system is located at the first portion and the second portion, and the effective diameter of the reflection element and the at least one lens is located at the first portion and does not extend to the second portion.

The effect of the present invention is that the design of the projection device can effectively achieve the purpose of reducing the volume and having high optical efficiency.

Drawings

Fig. 1 is a schematic view of a projection apparatus according to a preferred embodiment of the invention.

FIG. 2 is a schematic diagram of an image beam projected onto an image plane by a projection apparatus according to a preferred embodiment of the present invention.

Fig. 3 is a partially enlarged view of fig. 1.

Fig. 4 is a schematic view of a projection apparatus according to a second preferred embodiment of the invention.

Fig. 5 is a schematic view of a projection apparatus according to a third preferred embodiment of the invention.

Detailed Description

In order to more clearly illustrate the present invention, preferred embodiments will be described in detail below with reference to the accompanying drawings. Referring to fig. 1 to 3, a projection apparatus 100 according to a first preferred embodiment of the present invention is shown, the projection apparatus 100 is used for receiving an image light beam P generated by an image light source generating device 10 and projecting the image light beam P toward an imaging plane M, and forming a projection image on the imaging plane M, the projection apparatus 100 includes a relay optical system 20 and a reflective optical system 40 arranged along an optical axis.

The relay optical system 20 is configured to receive the image beam P and to allow the image beam P to pass through, the relay optical system 20 mainly includes a plurality of lenses, for example, in the present embodiment, the relay optical system 20 includes 9 lenses including lenses L1-L9, it is worth mentioning that an extending area of the optical axis a is divided into a first portion a1 and a second portion a2, effective diameters of the lenses L1-L9 of the relay optical system 20 are both located in the first portion a1 and the second portion a2, and the effective diameters refer to areas where the lenses L1-L9 actually pass through by the image beam P to cause optical performance change. In this way, the relay optical system 20 transmits the image beam P according to the designed optical effect, for example, but not limited to, optical design for correcting or compensating the self or caused chromatic aberration or aberrations such as spherical aberration, coma, astigmatism, field curvature, distortion, etc., or adjusting the light path, such as focusing, zooming, etc., can be designed. In other applications, the number of lenses, the shape of the lenses, etc. of the relay optical system 20 may be adjusted or changed according to different requirements of optical design or characteristics.

The reflective optical system 40 includes a reflective element LR and a lens L10, and in the present embodiment, only the lens L10 in the reflective optical system 40 has refractive power; the lens L10 is located between the reflective device LR and the relay optical system 20, and the lens L10 has a first optical surface S1 and a second optical surface S2 opposite to each other, and the second optical surface S2 faces the relay optical system 20, wherein after the relay optical system 20 receives the image light beam P, the image light beam P enters the lens L10 from the second optical surface S2, leaves the lens L10 from the first optical surface S1, is reflected by a reflective surface SR of the reflective device LR, enters the lens L10 from the first optical surface S1, and then leaves the lens L10 from the second optical surface S2 to project in the direction of the imaging surface M.

It should be noted that, in the embodiment, the image beam P enters the reflective optical system 40 from the first portion a1, and after leaving the lens L10 from the second optical surface S2, the image beam P is projected toward the imaging surface M through the second portion a2, so that the lens of the lens L10 and the reflective element LR can be cut or polished to make the effective diameters of the reflective element LR and the lens L10 located at the first portion a1 and not extending to the second portion a2 for the purpose of more effectively achieving the thinning.

In addition, when the lens of the lens L10 and the reflective element LR are made of plastic, the lens of the lens L10 and the reflective element LR can be directly molded into the shape with the effective diameter located in the first portion a1 by injection molding or die casting molding, so that the secondary machining operation of cutting or polishing is not required, and the weight can be reduced.

It should be noted that, the design in which the effective diameters of the reflective element LR and the lens L10 are located in the first portion a1 and do not extend to the second portion a2 not only achieves the effect of making the projection apparatus 100 compact and lightweight, but also greatly reduces the difficulty and precision requirements for assembling the projection apparatus 100, thereby reducing the assembly time and increasing the yield during assembly. In addition, in consideration of optical design, when the image beam P passes through the portion of the lens L10 located in the first portion a1, the image beam P is projected toward the direction of the image plane M without passing through the portion of the lens L10 located in the second portion a2 again, so that energy loss caused by multiple passes of the image beam P through different media can be reduced, projection quality can be improved, and the concern that partial light reflection is caused when the image beam P passes through the lens surface to interfere with optical performance can be reduced.

Referring to fig. 3, in the X-axis direction parallel to the optical axis a, the distance D1 between the reflective element LR and the lens L10 is smaller than the distance D2 between the lens L10 and the relay optical system 20, and the distance D1 between the reflective element LR and the lens L10 is greater than or equal to 0, which satisfies the condition that D1 is greater than or equal to 0mm, in practice, different conditions are selected for the application of the user-viewable projection apparatus, for example, when the projection apparatus is a large-scale projection apparatus, the condition that D1 is greater than or equal to 0mm is satisfied; when the projection device is a small projection device, the user can select the condition that D1 is more than or equal to 0mm and less than 4 mm; when the projection apparatus is a miniature projection device, a user may select a condition that D1 is greater than or equal to 0mm and less than 1mm, preferably, a condition that D1 is greater than or equal to 0mm and less than or equal to 0.6mm is satisfied, which is favorable for the miniaturization of the volume of the projection apparatus, in this embodiment, the reflective element LR is a mirror, the distance D1 between the reflective element LR and the lens L10 is the distance between the reflective element LR and the lens L10 on the optical axis, the distance D2 between the lens L10 and the relay optical system 20 is the distance between the lens L10 and the lens L9 on the optical axis, wherein D1 is 0.537 mm; d2 is 32.866mm, which is advantageous for the design of the projection apparatus 100 of the present invention to reduce the size and weight of the lens.

In the present embodiment, the absolute value of the curvature radius of the reflective surface SR of the reflective element LR is greater than the absolute value of the curvature radius of the first optical surface S1 of the lens L10, and preferably, the absolute value of the curvature radius of the first optical surface S1 of the lens L10 is greater than 10mm and less than 70 mm; in practice, when at least one of the reflective surface SR of the reflective device LR and the first optical surface S1 of the lens L10 is aspheric, the absolute value of the curvature radius of the reflective surface SR of the reflective device LR may be smaller than or equal to the absolute value of the curvature radius of the first optical surface S1 of the lens L10 by designing aspheric parameters.

In addition, the height Hm of the reflecting element LR in the Y-axis direction perpendicular to the optical axis a is a first effective height, where the first effective height Hm is the height from the optical axis to the maximum effective diameter of the reflecting element; the maximum height of the lens of the relay optical system 20 and the lens of the reflection optical system 40 in the direction perpendicular to the optical axis a is a second effective height HL, wherein the second effective height HL is the height from the optical axis to the maximum effective diameter of the lens of the relay optical system 20 and the lens of the reflection optical system 40, wherein the second effective height HL is between 0.7 times and 1.1 times the first effective height Hm, in the present embodiment, the first effective height Hm of the reflection element LR in the direction perpendicular to the optical axis is 21.5mm, the lens L10 of the reflection optical system 40 is the maximum height of the lens of the relay optical system 20 and the lens of the reflection optical system 40 in the direction perpendicular to the optical axis a, wherein the second effective height HL is 21.14mm, the second height HL is 0.98 times the first height Hm, thereby, by the design of the projection apparatus 100 of the present invention, it is beneficial to the miniaturization and light weight design of the lens.

The height of the reflective element LR is Hm in the Y-axis direction perpendicular to the optical axis; the length of the reflective element LR is Zm in the X-axis direction parallel to the optical axis, where Zm/Hm <0.6, preferably, the condition Zm/Hm <0.5 is satisfied, and in the present embodiment, Zm is 10.08 mm; the design that Hm is 21.5mm and Zm/Hm is 0.468mm, so that the reflecting element LR satisfies Zm/Hm <0.6, and the radius of curvature of the reflecting surface SR of the reflecting element LR is larger than the radius of curvature of the first optical surface S1 of the lens is advantageous for manufacturing the reflecting element LR, improving the manufacturing accuracy of the reflecting surface SR, reducing the sensitivity and suppressing aberration variation when the projection apparatus 100 is assembled, and obtaining preferable projection image performance.

In the embodiment, the reflective optical system 40 is only provided with the lens L10 and the reflective element LR, so that the number of lenses of the reflective optical system 40 can be reduced to reduce the cost, and the chance of generating unnecessary light reflection between the lenses can be reduced based on the reduction of the number of lenses, thereby improving the imaging quality. For other applications, the reflective optical system 40 may further include other optical elements without refractive power, such as a filter, and is not limited to the above description.

It should be noted that please refer to fig. 4, which is a second preferred embodiment of the present invention, and is similar to the first embodiment and will not be repeated herein, except that the distance D1 between the reflective device LR and the lens L10 is 0mm, more specifically, the reflective device LR is a metal reflective film layer of the lens L10 on the first optical surface S1, and the distance D1 between the reflective device LR and the lens L10 is equal to 0mm, so that the reflective surface SR of the reflective device LR and the first optical surface S1 are coplanar, that is, the absolute value of the curvature radius of the reflective surface SR of the reflective device LR is equal to the absolute value of the curvature radius of the first optical surface S1 of the lens L10, thereby reducing the number of times that light passes through different media, and reducing the light loss to achieve the effect of providing projection quality. Of course, in other applications, other reflective films may be used, and the material is not limited to the above, for example, a dielectric coating or a ceramic coating may be used to form the reflective film.

Please refer to fig. 5, which is a third preferred embodiment of the present invention, and is similar to the first embodiment and will not be repeated herein, except that the reflective optical system 40 is provided with a lens L11 and a lens L12, wherein the lens L11 has the second optical surface S2, the lens L12 has the first optical surface S1, the image beam P enters the lens L11 from the second optical surface S2, enters the reflective surface SR of the reflective element LR from the first optical surface S1, passes through the lens L12 and the lens L11 after being reflected by the reflective surface SR, exits the lens L11 from the second optical surface S2, and is projected in the direction of the imaging plane M, but the two lenses are designed to have effective diameters located in the first portion a1 and do not extend to the second portion a 2. Thus, the reflective element LR of the reflective optical system 40 of the present embodiment can be manufactured by increasing the curvature radius of the reflective surface SR or shortening the length Zm of the reflective element LR without affecting the optical performance through the refractive power design of the two lenses, which is more advantageous for the reflective element LR, and can effectively ensure the manufacturing accuracy of the reflective surface SR, reduce the sensitivity of the projector during assembling, and suppress the aberration variation.

It should be noted that the above-mentioned embodiments are only preferred and practical examples of the present invention, and all equivalent changes to the present invention as described and claimed should be included in the claims of the present invention.

Description of the reference numerals

[ invention ]

10 image light source generating device

100 projection device

20 relay optical system

L1-9 lens

40 reflective optical system

LR reflecting element

L10-12 lens

S1 first optical surface

S2 second optical surface

SR reflecting surface

Minimum distance D1

Minimum distance D2

Height Hm and HL

Length of Zm

P image beam

M image plane

A optical axis

A1 first part

A2 second part

X-axis and Y-axis

Claims

1. A projection device for receiving an image beam generated by an image light source generating device and projecting it in the direction of an imaging plane, the projection device comprising:

A relay optical system and a reflection optical system arranged along an optical axis; the relay optical system is used for receiving the image beam and allowing the image beam to pass through;

The reflective optical system includes a reflective element and at least one lens, and the at least one lens is located between the reflective element and the relay optical system, and has a first optical surface and a second optical surface opposite to each other optical surface, and the second optical surface faces the relay optical system;

Wherein, after the image beam passes through the relay optical system, the image beam enters the at least one lens from the second optical surface, and enters the reflection element from the first optical surface. a reflective surface, which passes through the at least one lens after being reflected by the reflective surface, leaves the at least one lens from the second optical surface, and projects in the direction of the imaging surface;

Wherein, in the direction parallel to the optical axis, the distance between the reflective element and the at least one lens on the optical axis is smaller than the distance between the at least one lens and the relay optical system on the optical axis , and the distance between the reflective element and the at least one lens on the optical axis is greater than or equal to 0;

Wherein, an extension plane of the optical axis is divided into a first part and a second part, the image beam is incident into the reflection optical system from the first part, and the image beam is emitted from the After the second optical surface leaves the at least one lens, it projects toward the imaging surface through the second part; in addition, the effective diameter of the relay optical system is located at the first part and the first part at the same time. The second part, and the effective diameter of the reflecting element and the at least one lens is located in the first part and does not extend to the second part.

2 . The projection device of claim 1 , wherein, in a direction parallel to the optical axis, the distance between the reflective element and the at least one lens is D1 , which satisfies 0mm≦D1<8mm. 3 .

3 . The projection apparatus of claim 1 , wherein a distance between the reflective element and the at least one lens on the optical axis is equal to 0. 4 .

4 . The projection device of claim 1 , wherein the reflective surface of the reflective element is attached to or plated on the first optical surface of the at least one lens. 5 .

5 . The projection device according to claim 1 , wherein the relay optical system has a plurality of lenses; wherein the height of the reflection element in a direction perpendicular to the optical axis is a first effective height; the relay optical system has a first effective height. 6 . Among the lens of the system and at least one lens of the reflective optical system, the highest height in the direction perpendicular to the optical axis is a second effective height, wherein the second effective height is 0.7 of the first effective height times to 1.1 times.

6. The projection device of claim 1, wherein a height of the reflective element in a direction perpendicular to the optical axis is a first effective height; at least one lens of the reflective optical system is in a direction perpendicular to the optical axis The height of is a second effective height, wherein the second effective height is between 0.7 times and 1.1 times the first effective height.

7 . The projection apparatus of claim 1 , wherein the number of the at least one lens is one, and the reflective optical system is composed of the reflective element and the lens. 8 .

8. The projection device of claim 1, wherein the absolute value of the radius of curvature of the reflection surface of the reflective element is greater than or equal to the absolute value of the radius of curvature of the first optical surface of the at least one lens.

9. The projection device according to claim 1, wherein at least one of the reflecting surface of the reflecting element and the first optical surface of the at least one lens is an aspheric surface, and the radius of curvature of the reflecting surface of the reflecting element The absolute value is less than or equal to the absolute value of the radius of curvature of the first optical surface of the at least one lens.

10. The projection device of claim 1, wherein the distance between the reflection element and the at least one lens on the optical axis is greater than 0, and the absolute value of the radius of curvature of the first optical surface of the at least one lens is greater than 10mm and less than 70mm.

11. The projection device of claim 1, wherein the distance between the reflecting element and the at least one lens on the optical axis is greater than 0, and the absolute value of the radius of curvature of the reflecting surface of the reflecting element is greater than 10 mm and less than 100mm.

12. The projection device according to claim 1, wherein, in the direction perpendicular to the optical axis, the height of the reflective element is Hm; in the direction parallel to the optical axis, the length of the reflective element is Zm, Among them, Zm/Hm<0.6.

13. The projection apparatus of claim 12, wherein Zm/Hm<0.5.