TWM592525U - Projector - Google Patents

Abstract

A projection device includes a light source, a light valve, and an optical lens. A reference point is provided on the projection optical axis of the projection device, the distance from the reference point to the projection imaging surface on the projection optical axis is R, and the distance from the light emitting position of the projection device to the reference point on the projection optical axis is L, when the reference point is located L is a positive value when the projection device is forward of the projection direction, and L is a negative value when the reference point is behind the projection device, and the optical lens satisfies one of the following conditions: (1) When 0.2≦L/R<1, the optical The error of the spherical imaging of the lens using the equal area projection method is less than 15%; (2) when -0.2≦L/R<0.2, the error of the spherical imaging of the optical lens using the isometric projection method is less than 15%; (3) when -0.6 ≦L/R<-0.2, the error of the spherical imaging of the optical lens using the spherical stereo projection method is less than 15%.

Description

Projector

The present invention relates to a projection device.

In recent years, various projection display technologies have been widely used in daily life. Generally speaking, the image projected by the projector onto the spherical projection screen is prone to distortion and deformation. Therefore, how to provide a good distortion correction optical design to obtain a correct image display effect is an important issue in the field of projection display.

The "prior art" paragraph is only used to help understand this new type of content. Therefore, the content disclosed in the "prior art" paragraph may include some conventional technologies that are not known to those with ordinary knowledge in the technical field to which they belong. The content disclosed in the "Prior Art" paragraph does not mean that the content or the problem to be solved by one or more embodiments of the present invention has been known or recognized by those with ordinary knowledge in the technical field before the application of the present invention.

Other objects and advantages of the present invention can be further understood from the technical features disclosed in the embodiments of the present invention.

According to an aspect of the present invention, a projection device is provided, which includes a light source, a light valve, and an optical lens. The light valve is disposed downstream of the light path of the light source, the optical lens is disposed downstream of the light path of the light valve, and the optical lens includes a first lens group with negative refractive power, a second lens group with positive refractive power, and a first lens group and An aperture between the second lens groups. A reference point is provided on the projection optical axis of the projection device, the distance from the reference point to a projection imaging plane on the projection optical axis is R, and the light emitting position of the projection device to the reference point is on the projection optical axis The distance above is L, when the reference point is in front of the projection direction of the projection device, L is a positive value, when the reference point is in the rear of the projection direction of the projection device, L is a negative value, when the reference point is in front of the projection direction of the projection device When L is a positive value, L is a negative value when the reference point is behind the projection direction of the projection device, and the optical lens satisfies one of the following conditions: (1) When 0.2≦L/R<1, the optical lens is used, etc. The spherical imaging error of the area projection method (equal-area projection) is less than 15%; (2) When -0.2≦L/R<0.2, the error of the spherical imaging of the optical lens using the azimuthal equidistant projection method is less than 15%; (3) When -0.6≦L/R<-0.2, the error of the spherical imaging of the optical lens using the stereographic projection method (stereographic projection) is less than 15%.

According to the above viewpoint of the present invention, the optical lens can have good optical imaging quality, and the optical lens can be used to project and image on a spherical projection screen or a dome cover, which can significantly reduce the amount of distortion of the projected image.

The other objects and advantages of the present invention can be further understood from the technical features disclosed by the present invention. In order to make the above-mentioned and other objects, features and advantages of the present invention more obvious and understandable, the embodiments are described in detail below in conjunction with the accompanying drawings, which are described in detail below.

10: Optical lens

10a, 10b, 10c: optical lens

12: First lens group

14: Second lens group

16: Optical axis

100: projection optical system

100a: projection device

110: Lighting system

112: Light source

112B: Blue light emitting diode

112G: Green light-emitting diode

112R: Red light emitting diode

114: Beam

114a: Sub-image

116: Light combining device

117: fly-eye lens array

118: Optical element group

119: Total reflection

120: light valve

121: glass cover

150: screen

150a: surface

E: Light position

r, r1, r2, r3: radius

L, R: distance

L1-L7: lens

S1-S19: Surface

S1’, S2’: the shortest distance

Y: Concentric circles

Y1, Y2, Y3: round

Y1’, Y2’, Y3’: projection pattern

O’: reference point

O: Ball center

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

2 is a schematic diagram of an optical lens according to an embodiment of the invention.

FIGS. 3, 4 and 5 are respectively the visible light sector diagram of the optical lens of FIG. 2, the ratio diagram of the illumination value of the image height position on the imaging plane and the illumination value of the optical axis position on the imaging plane, and the field curvature and distortion map.

6 is a schematic diagram of an optical lens according to another embodiment of the present invention.

FIG. 7, FIG. 8 and FIG. 9 are respectively the visible light sector diagram of the optical lens of FIG. 6, the ratio diagram of the illumination value of the image height position on the imaging plane and the illumination value of the optical axis position on the imaging plane, and the field curvature and distortion map.

10 is a schematic diagram of an optical lens according to another embodiment of the present invention.

11 is a schematic diagram illustrating the distortion correction performance of the projection device according to an embodiment of the present invention.

FIG. 12 is a diagram showing the relationship between half-view angle and image height of different projection methods.

The foregoing and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description with reference to the embodiments of the drawings. The direction words mentioned in the following embodiments, for example: up, down, left, right, front or back, etc., are only for the directions referring to the attached drawings. Therefore, the directional terms used are intended to illustrate rather than limit the new model. In addition, the terms "first" and "second" used in the following embodiments are used to identify the same or similar elements, and are not intended to limit the elements.

FIG. 1 is a schematic diagram of a projection optical system according to an embodiment of the present invention. Referring to FIG. 1, the projection optical system 100 includes an optical lens 10, an illumination system 110, a light valve 120, and a spherical screen 150. The lighting system 110 has a light source 112, which is adapted to provide a light beam 114, and the light valve 120 is disposed on the transmission path of the light beam 114. The light valve 120 is adapted to convert the light beam 114 into a plurality of sub-images 114a. In addition, the optical lens 10 is disposed on the transmission path of these sub-images 114 a, and the light valve 120 is located between the illumination system 110 and the optical lens 10. The light source 112 may include, for example, a red light-emitting diode 112R, a green light-emitting diode 112G, and a blue light-emitting diode 112B. The colored light emitted by each light-emitting diode is combined by a light combining device 116 to form a light beam 114. The light beam 114 may sequentially pass through a fly-eye lens array 117, an optical element group 118, and an internal total reflection TIR Prism 119. Thereafter, the internal total reflection prism 119 will reflect the light beam 114 to the light valve 120. At this time, the light valve 120 converts the light beam 114 into a plurality of sub-images 114a, and these sub-images 114a sequentially pass through the internal total reflection prism 119, and project the sub-images 114a on the spherical screen 150 through the optical lens 10 . In one embodiment, the spherical screen 150 may be a ball cover. In this embodiment, the projection display surface of the screen 150 may be formed by a partially spherical surface, but it is not limited.

FIG. 2 is a schematic diagram of the optical lens architecture of the first embodiment of the present invention. Please refer to FIG. 2, in this embodiment, the lens 10a has a lens barrel (not shown), and the first lens with negative refractive power is arranged from the first side (magnification side OS) to the second side (zoom side IS) in the lens barrel The lens group 12, the aperture S, and the second lens group 14 with positive refractive power. The first lens group 12 may include, for example, a first lens L1, a second lens L2, and a third lens L3, and the second lens group 14 may include, for example Four lens L4, fifth lens L5, and sixth lens L6. A light valve 120 is provided at the reduced side IS of the lens barrel, and a total reflection lens 119 and a cover glass 121 are provided between the light valve 120 and the second lens group 14, and the aperture S may be provided at the third Between the lens L3 and the fourth lens L4. In each embodiment of the present invention, the zoom-in side OS of the lens corresponds to the direction of the spherical screen 150, and the zoom-out side IS of the lens corresponds to the direction of the light valve 120, so the description will not be repeated.

The aperture S in the present invention refers to an aperture stop (Aperture Stop). The aperture S is an independent element or integrated on other optical elements. In this embodiment, the aperture uses a mechanism to block the surrounding light and keep the middle part to transmit light to achieve a similar effect, and the aforementioned so-called mechanism can be adjustable. The so-called adjustable refers to the adjustment of the position, shape or transparency of the mechanical parts. Alternatively, the aperture S can also be coated with an opaque light-absorbing material on the surface of the lens, and allow the central portion to transmit light to limit the optical path.

In this embodiment. The lens 10a includes six spherical lenses arranged along the optical axis 16, and the diopters of the dioptric power from the magnifying side OS to the zooming side IS are negative, negative, positive and negative, positive and positive, respectively. In this embodiment, each lens L1-L6 can be made of plastic or glass, and if the material of each lens L1-L6 is made of glass, a wider operating temperature range of, for example, -40 degrees to 105 degrees can be obtained. In addition, the two adjacent surfaces of the two lenses have approximately the same (half curvature Diameter difference is less than 0.005mm) or the same (substantially the same) radius of curvature and form a combined lens, cemented lens, doublet lens (doublet) or triplet lens (triplet), such as the fourth lens L4 and the fifth in this embodiment The lens L5 may constitute a cemented lens, but the present embodiment is not limited thereto.

The design parameters of the lens of the lens 10a and its peripheral components are shown in Table 1. However, the information listed below is not intended to limit the new model. Anyone with ordinary knowledge in the field after referring to the new model can make appropriate changes to its parameters or settings, but it should still fall within the scope of the new model. .

The radius of curvature in the table refers to the reciprocal of the curvature. When the curvature is positive, the center of the lens surface is in the direction of the reduction side of the lens. When the curvature is negative, the center of the lens surface is in the direction of the magnification side of the lens. The convexity and concavity of each lens can be seen in the above table and its corresponding diagram. When the new lens is used in a projection system, the imaging surface in the table is the surface of the light valve.

In this embodiment, when the field of view FOV is applied to a projection system, it refers to the angle between the optical surface closest to the magnification end and the optical axis of the lens, that is, the field of view measured diagonally. In this embodiment, the field of view FOV can be at most 116 degrees. In another embodiment, the FOV can be up to 110 degrees. In yet another embodiment, the FOV can be up to 100 degrees.

6 is a schematic diagram of a lens structure of a second embodiment of the present invention. As shown in FIG. 6, the lens 10 b includes a first lens group 12 with negative refractive power, an aperture S, and a second lens group 14 with positive refractive power, which are arranged from the enlargement side OS to the reduction side IS. In this embodiment, each lens L1-L6 may be a spherical lens and may be made of plastic or glass. The refractive powers of the lenses L1-L6 may be negative, negative, positive, positive, negative, and positive, respectively. The use of glass as the material of each lens L1-L6 can achieve a wide operating temperature range of, for example, -40 degrees to 105 degrees. In addition, the fourth lens L4 and the fifth lens L5 of this embodiment may constitute a cemented lens, but the The embodiment is not limited to this. In this embodiment, the design parameters of the lens and its peripheral components in the lens 10b are shown in Table 2.

10 is a schematic diagram of a lens structure of a third embodiment of the present invention. As shown in FIG. 10, the lens 10c includes 7 spherical lenses, and each lens L1-L7 may be made of plastic or glass, and the refractive powers of the lenses L1-L7 may be negative, negative, positive, positive, negative, positive, positive, respectively . The use of glass for the material of each lens L1-L7 can achieve a wide operating temperature range of, for example, -40 degrees to 105 degrees. In addition, the fourth lens L4 and the fifth lens L5 of this embodiment may constitute a cemented lens, but the present novel embodiment is not limited thereto. In this embodiment, the design parameters of the lens and its peripheral components in the lens 10c are shown in Table 3.

3, 4 and 5 are respectively a visible fan plot of the lens 10a according to an embodiment of the present invention, the ratio of the illumination value of the image height position on the imaging plane to the illumination value of the optical axis position on the imaging plane, and the field curvature and Distortion map. 7, 8 and 9 are respectively the visible light sector diagram of the lens 10b according to the embodiment of the present invention, the ratio of the illumination value of the image height position on the imaging surface and the illumination value of the optical axis position on the imaging surface, and the field curvature and Distortion map. The graphs shown in the simulation data graphs of FIGS. 3 to 5 and 7 to 9 are within the standard range, which can verify that the optical lens of this embodiment does have good optical imaging quality characteristics.

11 is a schematic diagram illustrating the distortion correction performance of the projection device according to an embodiment of the present invention. As shown in FIG. 11, in the projection optical system 100, the projection device 100a can project a pattern or an image onto a spherical screen 150, and the light valve 120 of the projection device 100a is provided. It is downstream of the light path of the light source (not shown), and the optical lens 10 can be provided downstream of the light path of the light valve 120. The projection optical axis 16 of the projection device 100a may be provided with a reference point O'. The reference point O'may be, for example, the spherical center O of the projection imaging surface of the spherical screen 150 (in this embodiment, the partially spherical surface 150a). In one embodiment, the distance from the reference point O′ to the projection imaging plane on the projection optical axis 16 is R, and the distance from the light emitting position E of the projection device 100a to the reference point O′ on the projection optical axis 16 is L, when the reference When the point O'is located in front of the projection direction of the projection device 100a (the reference point O'is closer to the screen 150 than the light emitting position), L is a positive value, and the reference point O'is located behind the projection direction of the projection device (the light emitting position E is compared to the reference When the point O'is close to the screen 150), L is a negative value. An optical lens according to an embodiment of the present invention can satisfy one of the following conditions: (1) When 0.2≦L/R<1, the optical lens uses the equal area projection method (equal- area projection) spherical imaging error is less than 15%; (2) when -0.2≦L/R<0.2, the optical lens using equidistant projection method (equidistant projection) spherical imaging error can be less than 15%; (3) when -0.6≦L/R<-0.2, the error of spherical imaging of optical lens using spherical stereo projection (stereographic projection) is less than 15%, the definition of error: absolute value of [(actual value-theoretical value of projection method)/projection method Theoretical value].

In another embodiment, the optical lens may satisfy one of the following conditions: (1) When 0.2≦L/R<1, the error of the spherical imaging of the optical lens using the equal-area projection method (equal-area projection) is less than 12%; (2) When -0.2≦L/R<0.2, the error of the spherical imaging of the optical lens using the equidistant projection method can be less than 12%; (3) When -0.6≦L/R<-0.2, the optical lens Spherical imaging using stereographic projection has an error of less than 12%. In yet another embodiment, the optical lens can satisfy one of the following conditions: (1) When 0.2≦L/R<1, the error of the spherical imaging of the optical lens using the equal-area projection method (equal-area projection) is less than 10%; (2) When -0.2≦L/R<0.2, the error of spherical imaging of the optical lens using the equidistant projection method can be less than 10%; (3) When -0.6≦L/R<-0.2, the optical lens Use spherical stereo projection (stereographic projection) spherical imaging error is less than 10%.

For example, the optical lens 10a shown in FIG. 2 has L/R=0.08, and the spherical imaging error using the isometric projection method is 3.05%. The various projection methods used by the above-mentioned optical lens are further described below. Generally speaking, projection methods applied to, for example, fisheye lenses may include, for example, orthogonal projection, equal-area projection, azimuthal equidistant projection, and stereo projection. (stereographic projection). Here, when the image height on the projection plane is specified as Y, the focal length of the entire optical system is specified as f, and the half angle of view is specified as ω, different projection methods can be expressed by the following expressions:

(A) Orthogonal projection method: Y=f×sin ω

(B) Equal area projection method: Y=2f×sin(ω/2)

(C) Isometric projection method: Y=f×ω

(D) Stereo projection method: Y=2f×tan(ω/2) Furthermore, FIG. 12 illustrates the half angle of view and the image height when the image height at a half angle of view of 90° is set to 1 in the projection method The relationship between them can be seen from FIG. 12 that different projection methods have different degrees of compression in the center and surrounding areas of the image. For example, in (A) orthogonal projection method, the peripheral compression degree of the image area is significantly higher, while in (D) stereo projection method, the center compression degree of the image area is significantly higher.

Please refer to FIG. 11 again. In an embodiment, the projection device 100a can project onto a part of the dome surface 150a having a spherical center O and a radius r. When the light emitting surface of the projection device 100a has the shortest distance from the light emitting surface to the part of the dome surface Between 50mm and 200mm, in an embodiment, when the center of the sphere O is to the right, the distance between the projection device 100a and the center of the sphere O is set to a positive value. When the projection device 100a is to the left of the center of the sphere O, The distance value between the projection device 100a and the spherical center O is set to a negative value. In this embodiment, the pattern Y to be projected may be a concentric circle formed by the first circle Y1, the second circle Y2, and the third circle Y3, the first circle Y1 The radius r1 of can be set to X cm, the radius r2 of the second circle Y2 is set to 2X cm, and the radius r3 of the third circle Y3 is set to 3X cm. When the pattern Y is projected onto the partial spherical surface 150a, the first The shortest distance from the projection pattern Y1' of a circle Y1 to the projection pattern Y2' of the second circle Y2 on the partial spherical surface 150a is S1', and the projection pattern Y2' of the second circle Y2 to the third circle Y3 The shortest distance of the projection pattern Y3' on the partial spherical surface 150a is S2', then the optical lens architecture according to an embodiment of the present invention can satisfy the condition that (S2'-S1')/S1' is less than 15%. In another embodiment, the optical lens may satisfy the condition that (S2'-S1')/S1' is less than 12%. In yet another embodiment, the optical lens may satisfy the condition that (S2'-S1')/S1' is less than 10%.

In one embodiment, the projection direction of the projection device 100a may be substantially parallel to the radial direction of the spherical surface 150a, and the shortest distance between the projection device 100a and the spherical center O in the radial direction of the partial spherical surface is -0.5r to r between. Furthermore, in an embodiment, the light exit position E of the projection device 100a may substantially coincide with the entrance pupil position of the optical lens 10.

The optical lens of the above embodiments can have good optical imaging quality, and the optical lens can be used to project and image on a spherical projection screen, which can significantly reduce the amount of distortion of the projected image.

The so-called light valve in this new type is a component that has been widely used and is a kind of spatial light modulator. The light valve can convert the illumination light into image light, such as DMD, LCD, LCOS, projection film, holographic film, mask with pattern, etc.

Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone who is familiar with this skill can make some changes and retouching without departing from the spirit and scope of the present invention. The scope of protection shall be as defined in the scope of the attached patent application. In addition, any embodiment of the present invention or the scope of patent application does not need to achieve all the purposes, advantages or features disclosed by the new model. In addition, the abstract part and title are only used to assist the search of patent documents, not to limit the scope of the rights of the new model.

10: Optical lens

16: Optical axis

100: projection optical system

100a: projection device

120: light valve

150: screen

150a: surface

E: Light position

r, r1, r2, r3: radius

L, R: distance

S1’, S2’: the shortest distance

Y: Concentric circles

Y1, Y2, Y3: round

Y1’, Y2’, Y3’: projection pattern

O’: reference point

O: Ball center

Claims (10)

A projection device includes: a light source; a light valve located downstream of the light path of the light source; and an optical lens located downstream of the light path of the light valve. The optical lens includes a first lens group with negative refractive power A second lens group with a positive refractive power and an aperture provided between the first lens group and the second lens group, wherein the first lens group includes a first lens and a second lens, and the second lens group Including a third lens and a fourth lens, the maximum field of view (FOV) of the optical lens is 116 degrees; wherein a reference point is provided on the projection optical axis of the projection device, and the reference point to a projection imaging plane is on the The distance on the projection optical axis is R, the distance from the light emitting position of the projection device to the reference point on the projection optical axis is L, when the reference point is located in front of the projection direction of the projection device, L is a positive value, when the When the reference point is behind the projection direction of the projection device, L is a negative value, and the optical lens satisfies one of the following conditions: (1) When 0.2≦L/R<1, the optical lens uses the equal-area projection method (equal-area The error of spherical imaging of projection) is less than 15%; (2) When -0.2≦L/R<0.2, the error of spherical imaging of the optical lens using azimuthal equidistant projection is less than 15%; (3) when -0.6≦L/R<-0.2, the error of the spherical imaging of the optical lens using the stereoscopic projection method (stereographic projection) is less than 15%, where the error is the absolute value of [(actual value-theoretical value of projection method)/projection Theoretical value]. The projection device as described in item 1 of the patent application range, wherein the distance L ranges from -0.5R to R. The projection device as described in item 1 of the patent application scope, wherein the light exit position of the projection device substantially coincides with the entrance pupil position of the optical lens. A projection device has an optical lens, the optical lens includes a first lens group with negative refractive power, a second lens group with positive refractive power, and a lens disposed between the first lens group and the second lens group Aperture, wherein the first lens group includes a first lens and a second lens, the second lens group includes a third lens and a fourth lens, wherein the projection device has a light exit surface and can project a pattern To a part of the dome surface, the shortest distance from the light emitting surface to the part of the dome surface is between 50mm and 200mm, wherein the pattern is formed by a first circle, a second circle, and a third circle Concentric circles, the radius of the first circle is X centimeters, the radius of the second circle is 2X centimeters, the radius of the third circle is 3X centimeters, when the pattern is projected onto the surface of the part of the dome, the The shortest distance from the first circular projection pattern to the second circular projection pattern on the surface of the dome cover is S1', and the second circular projection pattern to the third circular projection pattern is at the portion The shortest distance on the surface of the dome cover is S2', and the optical lens satisfies the condition of (S2'-S1')/S1'<15%. The projection device as described in item 4 of the patent application range, wherein the projection direction of the projection device is substantially parallel to the radial direction of the surface of the part of the dome cover. The projection device as described in item 1 or 4 of the patent application scope, wherein the optical lens further satisfies one of the following conditions: (1) The first lens group further includes a fifth lens, and the second lens group further includes a first Six lenses, (2) The first lens group further includes a fifth lens, and the second lens group further includes a sixth lens and a seventh lens. The projection device as described in item 6 of the patent application scope, wherein the optical lens further satisfies one of the following conditions: (1) The refractive power of the lens included in the first lens group is sequentially negative, negative, and positive in one direction, (2 ) The lens power of the second lens group is negative, positive, and positive in one direction, (2) The lens power of the second lens group is positive, negative, and positive in one direction. The projection device as described in item 6 of the patent application scope, wherein the optical lens is full One of the following conditions is satisfied: (1) the lens shape included in one direction is crescent, biconcave, crescent, crescent, biconvex, and biconvex, (2) the lens shape included in one direction is sequentially Crescent, plano-concave, plano-convex, bi-convex, crescent, bi-convex, (3) The lens shapes included in one direction are bi-concave, bi-concave, bi-convex, bi-convex, crescent, bi-convex, double Convex. The projection device as described in item 1 or 4 of the patent application scope, wherein all the lenses in the first lens group and the second lens group are spherical glass lenses. The projection device as described in item 1 or 4 of the patent application, wherein the second lens group further includes a cemented lens.

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