CN220305566U - Optical system and head-mounted device - Google Patents

Abstract

The application discloses an optical system and a head-mounted device. The optical system comprises at least two lenses arranged between a projection surface and an image source surface, a reflection polarization structure, a semi-transparent semi-reflection structure and a phase retarder, wherein the reflection polarization structure and the semi-transparent semi-reflection structure are arranged on different surfaces of the lenses in the at least two lenses, the reflection polarization structure is attached to the surfaces of the lenses, the reflection polarization structure is arranged between the semi-transparent semi-reflection structure and the projection surface, the phase retarder is arranged between the semi-transparent semi-reflection structure and the reflection polarization structure, and the surfaces of the lenses attached to the reflection polarization structure meet the following relational expression: the ratio of the salt to R is <0.1; the sag is the distance from the intersection point of the surface of the lens attached with the reflective polarizing structure and the optical axis to the maximum effective radius of the surface of the lens attached with the reflective polarizing structure in the direction parallel to the optical axis, and R is the curvature radius of the surface of the lens attached with the reflective polarizing structure at the optical axis. The optical system has higher yield in film pasting and increases the surface type freedom degree of the surface of the lens.

Description

Optical system and head-mounted device

Technical Field

The application relates to an optical imaging technology, in particular to an optical system and a head-mounted device.

Background

With the progress of technology and the need for socioeconomic development, the development of virtual reality technology has been rapid, and head-mounted devices (e.g., VR glasses) employing virtual reality technology have been developed. The optical system in the conventional head-mounted equipment comprises a plurality of lenses, a reflection polarization structure and a semi-transparent and semi-reflective structure, wherein the reflection polarization structure and the semi-transparent and semi-reflective structure are attached to different surfaces of the plurality of lenses to realize the turning back of the light path. When the surface of the lens attached by the reflective polarizing structure is aspheric, the film is attached by a curved surface film attaching method, in the curved surface film attaching process, the reflective polarizing structure is required to be heated first, tempering and slow cooling are required after heating in order to ensure that the characteristics of the reflective polarizing structure are not changed, but the film attaching time is long, so that the productivity is reduced, and the problems of wrinkling, air bubbles, warping and the like are also caused during film attaching, so that the film attaching yield is reduced.

Disclosure of Invention

In view of the foregoing, it is necessary to provide an optical system and a head-mounted device to solve the technical problems of long film sticking time and low film sticking yield.

An embodiment of the application provides an optical system, including locating two piece at least lenses between projection plane and the image source face, reflection polarization structure, half-transmission half-reflection structure and phase retarder, reflection polarization structure with half-transmission half-reflection structure locates the different surfaces of the lens in two piece at least lenses, reflection polarization structure pastes and locates the surface of lens, reflection polarization structure is located half-transmission half-reflection structure with between the projection plane, phase retarder locates half-transmission half-reflection structure with between the reflection polarization structure, reflection polarization structure pastes the surface of establishing the lens satisfies following relational expression:

0<|sag/R|<0.1；

The sag is a distance from an intersection point of the surface of the lens attached with the reflective polarizing structure and the optical axis to the maximum effective radius of the surface of the lens attached with the reflective polarizing structure, wherein the distance is parallel to the optical axis direction, and R is a curvature radius of the surface of the lens attached with the reflective polarizing structure at the optical axis.

According to the optical system, the surface of the lens attached with the reflective polarizing structure is set to be the micro-curved surface meeting the relation, and as the micro-curved surface is small in bending and small in stress, the influence on the characteristics of the reflective polarizing structure is small in film attaching, the film attaching yield is high, the film attaching process is simple, the film attaching time is short, the film attaching efficiency is improved, and in addition, the micro-curved surface is set to further increase the surface type freedom degree of the surface of the lens, so that the optical effect of the optical system is improved.

In some embodiments, the optical system includes a first lens and a second lens disposed in sequence between a projection plane and an image source plane, the reflective polarizing structure is disposed on an image source side of the first lens or a projection side of the second lens, and the transflective structure is disposed on an image source side of the first lens or an image source side of the second lens or a projection side of the second lens.

Therefore, the reflection polarizing structure and the semi-transparent and semi-reflective structure can be arranged on different surfaces of the two lenses, and the attaching positions of the reflection polarizing structure and the semi-transparent and semi-reflective structure are flexible.

In some embodiments, the optical system includes a first lens, a second lens and a third lens sequentially disposed between a projection plane and an image source plane, the reflective polarizing structure is disposed on an image source side of the first lens, or a projection side of the first lens, or an image source side of the second lens, or a projection side of the third lens, and the transflective structure is disposed on a projection side of the first lens, or an image source side of the second lens, or a projection side of the third lens, or an image source side of the third lens.

Therefore, the reflection polarizing structure and the semi-transparent and semi-reflective structure can be arranged on different surfaces of the three lenses, and the attaching positions of the reflection polarizing structure and the semi-transparent and semi-reflective structure are flexible.

In some embodiments, the optical system includes a first lens, a second lens, a third lens, and a fourth lens sequentially disposed between a projection plane and an image source plane, the reflective polarizing structure is disposed on an image source side of the first lens, or on a projection side of the second lens, or on a projection side of the third lens, or on a projection side of the fourth lens, and the semi-transparent semi-reflective structure is disposed on an image source side of the first lens, or on an image source side of the second lens, or on a projection side of the third lens, or on a projection side of the fourth lens, or on an image source side of the fourth lens.

Therefore, the reflection polarizing structure and the semi-transparent and semi-reflective structure can be arranged on different surfaces of the four lenses, and the attaching positions of the reflection polarizing structure and the semi-transparent and semi-reflective structure are flexible.

In some embodiments, the phase retarder is disposed on a light-transmitting surface of the lens or a light-transmitting surface of the reflective polarizing structure, and the phase retarder and the transflective structure are disposed on different surfaces.

In this way, the phase retarder can rotate polarized light emitted by the reflective polarizing structure, so as to adjust the polarization direction of the polarized light.

In some embodiments, the phase retarder and the reflective polarizing structure are laminated and arranged on the light transmitting surface of the lens correspondingly arranged.

Therefore, the pasting process is convenient.

In some embodiments, the optical system satisfies the following conditional expression:

85°<FOV<100°；

wherein FOV is the maximum field angle of the optical system; and/or the optical system satisfies the following relationship:

35mm<Dmax<55mm；

wherein Dmax is the maximum optical effective diameter of a lens of the at least two lenses; and/or the at least two lenses comprise a first lens adjacent to the projection surface, the optical system satisfying the following conditional expression:

10mm<TTL<22mm；

Wherein TTL is a distance between a projection side of the first lens and the image source surface of the optical system on an optical axis; and/or the at least two lenses comprise a first lens close to the projection surface, the optical system further comprises a diaphragm arranged between the first lens and the projection surface, and the optical system meets the following conditional expression:

T1≧10mm；

wherein T1 is the distance between the diaphragm and the projection side of the first lens on the optical axis; and/or the optical system satisfies the following conditional expression:

8mm≦EyeBox≦11mm；

wherein, the EyeBox is the eye box of the optical system.

By satisfying the relation 85 ° < FOV <100 °, the field angle of the optical system can be made larger, and the imaging quality is ensured. However, when the FOV is less than or equal to 85 degrees, the practical value is not available; when the FOV is more than or equal to 100 degrees, the process difficulty is high, the cost is high, and the distortion and the lens size are too large, so that the miniaturization of an optical system is not facilitated. By satisfying the relation 35mm < Dmax <55mm, the aberration convergence of the optical system is better, the imaging quality is ensured, and the miniaturization of the optical system is facilitated. By satisfying the relation 10mm < TTL <22mm, the size of the optical system can be ensured not to be too large, thereby facilitating miniaturization of the head-mounted device in which the optical system is mounted. However, when TTL. Gtoreq.22 mm, the size of the optical system is large, thereby making the size of the head-mounted device in which the optical system is mounted large. By satisfying the relation T1 ∈ 10mm, the distance between the human eye and the lens can be made appropriate, and the imaging quality is good. However, when T1<10mm, the distance between the human eye and the lens is small, and the lens easily interferes with the eye. By satisfying the relation 8 < EyeBox < 11, the imaging quality can be ensured, and better immersion experience can be obtained. However, if the pupil is out of the above range, the error tolerance of the displacement is small when the pupil and the head-mounted device are relatively moved, and the image quality is easily deteriorated when moved, thereby affecting the imaging quality.

In some embodiments, the optical system satisfies the following relationship:

1<Dmax/(2*IH)<1.5；

wherein, in the optical system, the maximum optical effective diameter in the projection side and the image source side of all lenses is Dmax, and IH is the image height corresponding to the maximum field angle of the optical system; and/or the optical system satisfies the following relationship:

1.54<(2*EFL)/IH<5；

wherein EFL is the effective focal length of the optical system; and/or the at least two lenses comprise a first lens adjacent to the projection surface, the optical system satisfying the following conditional expression:

0.4<TTL/(2*IH)<0.7；

wherein TTL is a distance between a projection side of the first lens and the image source plane of the optical system on an optical axis.

By satisfying the relation 1< dmax/(2×ih) <1.5, the aberration convergence of the optical system can be made good, and the imaging quality is ensured, which is advantageous for miniaturization of the optical system. However, when Dmax/(2×ih) > 1.5, not only the aberration is contained, but also the size of the optical system is large. By satisfying the relation 1.54< (2 x EFL)/IH <5, the aberration convergence of the optical system can be better, the imaging quality is ensured, and the miniaturization of the optical system is facilitated. However, when (2×efl)/IH is less than or equal to 1.54, the aberration convergence of the optical system is poor; when IH/(2×EFL) is not less than 5, the size of the optical system can be greatly reduced, which is advantageous for miniaturization of the optical system. By satisfying the relation 0.4< ttl/(2×ih) <0.7, the size of the optical system 100 can be ensured not to be too large, thereby facilitating miniaturization of the head-mounted apparatus in which the optical system 100 is mounted. However, when TTL/(2×ih) ttl+.0.4 or 0.7mm < TTL/(2×ih), the size of the optical system 100 is large, so that the size of the head-mounted device in which the optical system 100 is mounted is large.

In some embodiments, the at least two lenses include a first lens proximate to the projection surface and a second lens disposed between the first lens and the image source surface, and the optical system satisfies the following conditional expression:

1≦CT1/ET1≦2.5；

wherein CT1 is the distance between the projection side of the first lens and the image source side of the first lens on the optical axis, and ET1 is the distance between the maximum optical effective caliber of the first lens and the direction parallel to the optical axis; and/or the optical system satisfies the following conditional expression:

0.6≦CT2/ET2≦2.5；

wherein CT2 is the distance between the projection side of the second lens and the image source side of the second lens on the optical axis, and ET2 is the distance between the maximum optical effective aperture of the second lens and the direction parallel to the optical axis.

By satisfying the relation 1 < CT1/ET1 < 2.5, the thickness ratio of the first lens can be reasonably controlled, the molding difficulty of the first lens is reduced, the processing sensitivity is reduced, and the production yield is improved. However, if outside the above range, the first lens molding difficulty is high. By satisfying the relation of 0.6 less than or equal to CT2/ET2 less than or equal to 2.5, the thickness ratio of the second lens can be reasonably controlled, the forming difficulty of the second lens is reduced, the processing sensitivity is reduced, and the production yield is improved. However, if the second lens is out of the above range, the second lens molding difficulty is high.

An embodiment of the application further provides a head-mounted device, which comprises a shell, a display and the optical system, wherein the display and the optical system are arranged on the shell, and the display is positioned on an imaging surface of the optical system.

The head-mounted device comprises an optical system, wherein the surface of a lens attached with the reflective polarizing structure is set to be a micro-curved surface meeting the relation, and the micro-curved surface is small in bending and stress, so that the influence on the characteristics of the reflective polarizing structure is small in film attaching, the film attaching yield is high, the film attaching process is simple, the film attaching time is short, the film attaching efficiency is improved, and in addition, the micro-curved surface is set to increase the surface type freedom degree of the surface of the lens, so that the optical effect of the optical system is improved.

Drawings

Fig. 1 is a block diagram of an optical system according to an embodiment of the present application.

Fig. 2 is a structural diagram of an optical system of the first embodiment of the present application.

Fig. 3 is an astigmatism and distortion graph of an optical system of a first embodiment of the present application.

Fig. 4 is a structural diagram of an optical system of a second embodiment of the present application.

Fig. 5 is an astigmatism and distortion graph of an optical system according to a second embodiment of the present application.

Fig. 6 is a structural diagram of an optical system of a third embodiment of the present application.

Fig. 7 is an astigmatism and distortion graph of an optical system according to a third embodiment of the present application.

Fig. 8 is a structural diagram of an optical system of a fourth embodiment of the present application.

Fig. 9 is an astigmatism and distortion graph of an optical system of a fourth embodiment of the present application.

Fig. 10 is a structural diagram of an optical system of a fifth embodiment of the present application.

Fig. 11 is an astigmatism and distortion graph of an optical system of a fifth embodiment of the present application.

Fig. 12 is a structural diagram of an optical system of a sixth embodiment of the present application.

Fig. 13 is an astigmatism and distortion graph of an optical system of a sixth embodiment of the present application.

Fig. 14 is a schematic perspective view of a headset according to an embodiment of the present application.

Description of the main reference signs

Optical system 100

First lens L1

Second lens L2

Third lens L3

Fourth lens L4

Reflective polarizing structure 10

Semi-transparent and semi-reflective structure 20

Phase retarder 30

Optical filter 40

Diaphragm 101

Image source surface 102

Projection sides 11, 13, 15, 17

Image source sides 12, 14, 16, 18

Head-mounted device 200

Housing 201

Optical axis O

Detailed Description

Embodiments of the present application are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

Referring to fig. 1, an embodiment of the present application provides an optical system 100, which includes a first lens L1, a reflective polarizing structure 10, a second lens L2, and a transflective structure 20 disposed between a projection plane and an image source plane 102. The reflection polarization structure 10 and the semi-transparent and semi-reflective structure 20 are arranged on different surfaces of the lenses in the first lens L1 and the second lens L2, the reflection polarization structure 10 is attached to the surface of the lens, the reflection polarization structure 10 is arranged between the semi-transparent and semi-reflective structure 20 and the projection surface, and the surface of the lens attached to the reflection polarization structure 10 meets the following relation:

0<|sag/R|<0.1；

The sag is a distance from an intersection point of the surface of the lens attached with the reflective polarizing structure 10 and the optical axis O to a maximum effective radius of the surface of the lens attached with the reflective polarizing structure 10 in a direction parallel to the optical axis O, and R is a radius of curvature of the surface of the lens attached with the reflective polarizing structure 10 at the optical axis O.

In the optical system 100, the surface of the lens to which the reflective polarizing structure 10 is attached is a micro-curved surface satisfying the above relationship, and since the micro-curved surface is slightly curved and the stress is also small, the influence on the characteristics of the reflective polarizing structure 10 itself is small during film attachment, and the film attachment yield is high; in addition, the micro-curved surface is arranged to increase the surface type freedom degree of the surface of the lens, so that the optical effect of the optical system 100 is improved.

In this embodiment, the semi-transparent and semi-reflective structure 20 is plated on the surface of the lens. It will be appreciated that in other embodiments, the transflective structure 20 is attached to the surface of the lens.

In the present embodiment, the reflective polarizing structure 10 is a multilayer reflective polarizing film and is adhered to the image source side 12 of the first lens L1 by glue. The transflective structure 20 is a transflective film and is attached to the image source side 14 of the second lens L2 by glue.

In some embodiments, the optical system 100 further includes a retarder 30, where the retarder 30 is disposed on a light-transmitting surface of the lens or a light-transmitting surface of the reflective polarizing structure 10, and the retarder 30 and the transflective structure 20 are disposed on different surfaces, and are used for rotating polarized light emitted by the reflective polarizing structure 10 by a predetermined angle to adjust a polarization direction of the polarized light. In the present embodiment, the phase retarder 30 is a quarter-wave plate and is attached to the projection side 13 of the second lens L2 by glue. In this way, the phase retarder 30 can rotate the polarized light emitted from the reflective polarizing structure 10, thereby adjusting the polarization direction of the polarized light. In some embodiments, the phase retarder 30 is laminated with the reflective polarizing structure 10 on the light-transmitting surface of the corresponding lens. Therefore, the pasting process is convenient.

In some embodiments, the optical system 100 further includes a filter 40, where the filter 40 is disposed on a side of the image source surface 102 near the second lens L2 to filter stray light.

In some embodiments, the optical system 100 satisfies the following conditional expression:

85°<FOV<100°；

where FOV is the maximum field angle of the optical system 100.

By satisfying the above-described relational expression, the angle of view of the optical system 100 can be made large, and the imaging quality can be ensured. However, when the FOV is less than or equal to 85 degrees, the practical value is not available; when the FOV is not less than 100 °, the difficulty of the processing process is high, the cost is high, and the distortion and the lens size are too large, which is not beneficial to miniaturization of the optical system 100.

In some embodiments, the optical system 100 satisfies the following relationship:

1<Dmax/(2*IH)<1.5；

where Dmax is the maximum optical effective diameter of the lens out of the at least two lenses, and IH is the image height corresponding to the maximum field angle of the optical system 100.

By satisfying the above relation, the aberration of the optical system 100 can be converged well, the imaging quality is ensured, and the miniaturization of the optical system 100 is facilitated. However, when Dmax/(2×ih) > 1.5, not only the aberration is contained, but also the size of the optical system 100 is large.

In some embodiments, the optical system 100 satisfies the following relationship:

1.54<(2*EFL)/IH<5；

wherein EFL is the effective focal length of the optical system 100.

By satisfying the above relation, the aberration of the optical system 100 can be converged well, the imaging quality is ensured, and the miniaturization of the optical system 100 is facilitated. However, (2×efl)/IH is less than or equal to 1.54, the aberration of the optical system 100 is less converged; when (2×efl)/ih+.5, the size of the optical system 100 is increased, which is disadvantageous for miniaturization of the optical system 100.

In some embodiments, the optical system 100 satisfies the following relationship:

35mm<Dmax<55mm；

by satisfying the above relation, the aberration of the optical system 100 can be converged well, the imaging quality is ensured, and the miniaturization of the optical system 100 is facilitated.

In some embodiments, the optical system 100 satisfies the following conditional expression:

10mm<TTL<22mm；

the TTL is a distance between the projection side 11 of the first lens L1 and the image source surface 102 of the optical system 100 on the optical axis O. The projection side is a side of the lens away from the image source surface 102.

By satisfying the above relation, the size of the optical system 100 can be ensured not to be too large, thereby facilitating miniaturization of the head-mounted apparatus in which the optical system 100 is mounted. However, when TTL. Gtoreq.22 mm, the size of the optical system 100 is large, thereby making the size of the head-mounted device in which the optical system 100 is mounted large.

In some embodiments, the optical system 100 satisfies the following conditional expression:

0.4<TTL/(2*IH)<0.7；

by satisfying the above relation, the size of the optical system 100 can be ensured not to be too large, thereby facilitating miniaturization of the head-mounted apparatus in which the optical system 100 is mounted. However, when TTL/(2×ih) ttl+.0.4 or 0.7mm < TTL/(2×ih), the size of the optical system 100 is large, so that the size of the head-mounted device in which the optical system 100 is mounted is large.

In some embodiments, the optical system 100 further includes a diaphragm 101 disposed between the first lens L1 and the projection surface, and the optical system 100 satisfies the following conditional expression:

T1≧10mm；

Wherein T1 is a distance between the diaphragm 101 and the projection side of the first lens L1 on the optical axis O.

By satisfying the above relation, the distance between the human eye and the lens can be made appropriate, and the imaging quality is improved. However, when T1<10mm, the distance between the human eye and the lens is small, and the lens easily interferes with the eye.

In some embodiments, the optical system 100 satisfies the following conditional expression:

1≦CT1/ET1≦2.5；

wherein, CT1 is the distance between the projection side of the first lens L1 and the image source side 12 of the first lens L1 on the optical axis O, and ET1 is the distance between the maximum optical effective aperture of the first lens L1 and the direction parallel to the optical axis O. The image source side 12 of the first lens L1 is a side of the first lens L1 near the image source surface 102.

Through satisfying above-mentioned relational expression, can rationally control the thickness ratio of first lens L1, reduce the shaping degree of difficulty of first lens L1 to the processing sensitivity that reduces improves the production yield. However, if the amount is outside the above range, the molding difficulty of the first lens L1 is high.

In some embodiments, the optical system 100 satisfies the following conditional expression:

0.6≦CT2/ET2≦2.5；

wherein CT2 is the distance between the projection side 13 of the second lens L2 and the image source side 14 of the second lens L2 on the optical axis O, and ET2 is the distance between the maximum optical effective aperture of the second lens L2 and the direction parallel to the optical axis O.

Through satisfying above-mentioned relational expression, can rationally control the thickness ratio of second lens L2, reduce the shaping degree of difficulty of second lens L2 to the processing sensitivity that reduces improves the production yield. However, if the second lens L2 is out of the above range, the molding difficulty of the second lens L2 is high.

In some embodiments, the optical system 100 satisfies the following conditional expression:

8≦EyeBox≦11；

the EyeBox is an eye box of the optical system 100, that is, an exit pupil aperture of the optical system 100.

By meeting the relation, the imaging quality can be ensured, and better immersion experience is obtained. However, if the pupil is out of the above range, the error of the offset is allowed to be small when the pupil and the head-mounted device 200 are relatively moved, and the image quality is easily deteriorated when moved, thereby affecting the imaging quality.

In some embodiments, at least one lens of the optical system 100 has an aspherical profile. In one embodiment, either the projection side or the image source side of each lens may be designed to be aspherical. The aspheric design can help the optical system 100 to more effectively eliminate aberrations and improve imaging quality. In some embodiments, at least one lens in the optical system 100 may also have a spherical surface shape, and the design of the spherical surface shape may reduce the difficulty of manufacturing the lens and reduce the manufacturing cost. In some embodiments, in order to achieve the advantages of manufacturing cost, manufacturing difficulty, imaging quality, assembly difficulty, etc., the design of each lens surface in the optical system 100 may be composed of an aspherical surface and a spherical surface.

The surface type calculation of the aspherical surface can refer to an aspherical surface formula:

wherein Z is the distance from the corresponding point on the aspheric surface to the tangential plane of the surface at the optical axis O, r is the distance from the corresponding point on the aspheric surface to the optical axis O, c is the refractive index of the aspheric surface at the optical axis O, k is the conic coefficient, and Ai is the higher order term coefficient corresponding to the i-th order higher order term in the aspheric surface formula.

In some embodiments, at least one lens of the optical system 100 is made of Plastic (PC), which may be polycarbonate, gum, or the like. In some embodiments, the material of at least one lens in the optical system 100 is Glass (GL). The lens with plastic material can reduce the production cost of the optical system 100, while the lens with glass material can withstand higher or lower temperature and has excellent optical effect and better stability. In some embodiments, lenses of different materials may be disposed in the optical system 100, i.e. a combination of glass lenses and plastic lenses may be used, but the specific configuration relationship may be determined according to practical requirements, which is not meant to be exhaustive.

In some embodiments, the optical system 100 further includes a diaphragm 101, where the diaphragm 101 may also be a field diaphragm 101, and the diaphragm 101 is used to control the light entering amount and the depth of field of the optical system 100, and meanwhile, can also achieve good interception of the non-effective light to improve the imaging quality of the optical system 100, and may be disposed between the projection surface of the optical system 100 and the projection side of the first lens L1. It should be understood that in other embodiments, the diaphragm 101 may be disposed between two adjacent lenses, for example, between the first lens L1 and the second lens L2, and the arrangement is adjusted according to the actual situation, which is not particularly limited in this embodiment. The diaphragm 101 may also be formed by a clamp to secure the lens.

The optical system 100 of the present application is described below by way of more specific examples:

first embodiment

Referring to fig. 2, in the optical system 100 of the present embodiment, the optical system includes, in order from a projection plane to an image source plane 102 along an optical axis O, a diaphragm 101, a first lens L1 with positive refractive power, a reflective polarizing structure 10, a second lens L2 with negative refractive power, a transflective structure 20, and an optical filter 40. Wherein the reflective polarizing structure 10 is a composite film composed of a linear polarizing film for polarization detection and a polarizing reflecting film for reflection.

The projection side 11 of the first lens L1 is convex at the paraxial region O, and the image source side 12 of the first lens L1 is convex at the paraxial region O. The projection side 13 of the second lens L2 is convex at the paraxial region O and the image source side 14 of the second lens L2 is convex at the paraxial region O.

In use, light from the image source surface 102, after passing through the filter 40, the transflective structure 20, the second lens L2 and the reflective polarizing structure 10 in order, is screened and deflected on the reflective polarizing structure 10, that is, after polarization splitting is performed by the reflective polarizing structure 10 and a part of the polarized light is changed in direction, the part of the polarized light is folded back and passes through the second lens L2, and then, the polarized light is reflected on the transflective structure 20, so that the polarized light is folded back on the image source side of the second lens L2 and passes through the second lens L2, the reflective polarizing structure 10 and the first lens L1 in order, and finally, is incident on the projection surface.

The lens parameters of the optical system 100 in this embodiment are shown in table 1 below. The elements from the projection surface of the optical system 100 to the image source surface 102 are arranged in the order from top to bottom in table 1, where STO represents the diaphragm 101. The radius Y in table 1 is the radius of curvature of the corresponding surface of the lens at the optical axis O. In table 1, the surface with the surface number S1 represents the projection side 11 of the first lens L1, the surface with the surface number S2 represents the image source side 12 of the first lens L1, and so on. The absolute value of the first value of the lens in the "thickness" parameter column is the thickness of the lens on the optical axis O, wherein the direction from the projection plane to the image source plane is default to be positive, the thickness is positively signed, and otherwise, the thickness is negatively signed. The absolute value of the second value is the distance between the image source side of the lens and the subsequent optical surface (the projection side of the subsequent lens) on the optical axis O, wherein the thickness parameter of the diaphragm 101 represents the distance between the diaphragm 101 surface and the projection side of the adjacent lens on the image source side on the optical axis O. The refractive index and Abbe number of each lens in the table are 540nm, the focal length is 540nm, and the Y radius, thickness and focal length are all in millimeters (mm). The three-in-one film in the table is formed by compounding two quarter wave plates and a polaroid arranged between the quarter wave plates, so that the light source efficiency can be improved, the anti-reflection effect is better, and it can be understood that in other embodiments, the three-in-one film can also be formed by compounding other types of wave plates and polaroids, so long as the technical effect can be met, and the description is omitted. The parameter data and lens surface type structure used for relational computation in the following embodiments are based on the data in the lens parameter table in the corresponding embodiments.

TABLE 1

Table 2 below presents the aspherical coefficients of the corresponding lens surfaces in table 1, where K is a conic coefficient and Ai is a coefficient corresponding to the i-th order higher order term in the aspherical surface type formula.

TABLE 2

Face number

K

A4

A6

A8

A10

A12

S1

0.00000E+00

1.19083E-05

-2.34609E-08

3.72317E-11

-2.62396E-14

0.00000E+00

S2

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S3

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S4

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S5

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S6

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S7

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S8

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S9

7.71776E+01

-1.85496E-06

8.46630E-09

-4.35272E-11

5.57377E-14

-2.44116E-17

S10

0.00000E+00

1.00339E-06

3.10746E-09

-9.73519E-12

5.31973E-15

3.03766E-18

S11

7.71776E+01

-1.85496E-06

8.46630E-09

-4.35272E-11

5.57377E-14

-2.44116E-17

S12

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S13

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S14

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S15

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S16

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S17

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S18

-5.26382E+01

1.55399E-06

5.99530E-10

4.20214E-14

-3.55265E-15

0.00000E+00

S19

7.71776E+01

-1.85496E-06

8.46630E-09

-4.35272E-11

5.57377E-14

-2.44116E-17

S20

0.00000E+00

1.00339E-06

3.10746E-09

-9.73519E-12

5.31973E-15

3.03766E-18

Referring to fig. 3, the left side of fig. 3 shows the light astigmatism diagrams of the optical system 100 in the first embodiment at wavelengths of 623nm, 546nm, 454 nm. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatic curves represent the meridional imaging plane curvature T and the sagittal imaging plane curvature S, and it can be seen from the optical system 100 in fig. 3 that the maximum values of the arc-loss field curvature and the meridional field curvature are both smaller than 0.2mm, at which wavelength the astigmatism of the optical system 100 is well compensated.

The right-hand graph in fig. 3 is a distortion graph of the optical system 100 in the first embodiment at a wavelength of 546 nm. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from the right-hand graph in fig. 3, the maximum distortion is less than 30% at a wavelength of 546nm, and the distortion of the optical system 100 is well corrected.

Second embodiment

Referring to fig. 4, in the optical system 100 of the present embodiment, the aperture stop 101, the reflective polarizing structure 10, the first lens L1 with positive refractive power, the second lens L2 with negative refractive power, the transflective structure 20 and the optical filter 40 are sequentially disposed along the optical axis O from the projection plane to the image source plane 102. Wherein the reflective polarizing structure 10 is a composite film composed of a linear polarizing film and a polarizing reflective film.

The projection side 11 of the first lens L1 is concave at the paraxial region O and the image source side 12 of the first lens L1 is convex at the paraxial region O. The projection side 13 of the second lens L2 is convex at the paraxial region O and the image source side 14 of the second lens L2 is convex at the paraxial region O.

In use, after passing through the optical filter 40, the semi-transparent and semi-reflective structure 20, the second lens L2, the first lens L1 and the reflective polarizing structure 10 in order, the light from the image source surface 102 is screened and deflected on the reflective polarizing structure 10, that is, after polarized light is split by the reflective polarizing structure 10 and the direction of part of the polarized light is changed, part of the polarized light is folded back and passes through the first lens L1 and the second lens L2, and then the polarized light is reflected on the semi-transparent and semi-reflective structure 20, so that the polarized light is folded back on the image source side 14 of the second lens L2 and passes through the second lens L2, the first lens L1 and the reflective polarizing structure 10 in order, and finally enters the projection surface.

The parameters of each lens of the optical system 100 in this embodiment are given in table 3, wherein the names and parameters of each element can be defined in the first embodiment, and are not described herein.

TABLE 3 Table 3

TABLE 4 Table 4

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Referring to fig. 5, the left side of fig. 5 shows the light astigmatism diagrams of the optical system 100 in the second embodiment at wavelengths of 623nm, 546nm, 454 nm. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatic curves represent the meridional imaging plane curvature T and the sagittal imaging plane curvature S, and it can be seen from the optical system 100 in fig. 5 that the maximum values of the arc-loss field curvature and the meridional field curvature are both smaller than 0.2mm, at which wavelength the astigmatism of the optical system 100 is well compensated.

The right-hand graph in fig. 5 is a distortion graph of the optical system 100 in the second embodiment at a wavelength of 546 nm. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from the right-hand graph in fig. 5, the maximum distortion is less than 30% at a wavelength of 546nm, and the distortion of the optical system 100 is well corrected.

Third embodiment

Referring to fig. 6, in the optical system 100 of the present embodiment, the optical system includes, in order from the projection plane to the image source plane 102 along the optical axis O, a diaphragm 101, a first lens L1 with positive refractive power, a reflective polarizing structure 10, a second lens L2 with negative refractive power, a transflective structure 20, and an optical filter 40. Wherein the reflective polarizing structure 10 is a composite film composed of a linear polarizing film and a polarizing reflective film.

The projection side 11 of the first lens L1 is convex at the paraxial region O, and the image source side 12 of the first lens L1 is convex at the paraxial region O. The projection side 13 of the second lens L2 is convex at the paraxial region O and the image source side 14 of the second lens L2 is convex at the paraxial region O.

In use, after light from the image source surface 102 passes through the filter 40, the transflective structure 20, the second lens L2 and the reflective polarizing structure 10 in order, light is screened and deflected on the reflective polarizing structure 10, that is, after polarization splitting is performed by the reflective polarizing structure 10 and a part of the polarized light is changed in direction, part of the polarized light is folded back and passes through the second lens L2, and then, the polarized light is reflected on the transflective structure 20, so that the polarized light is folded back on the image source side 14 of the second lens L2 and passes through the second lens L2, the reflective polarizing structure 10 and the first lens L1 in order, and finally, is incident on the projection surface.

The lens parameters of the optical system 100 in this embodiment are given in table 5, wherein the definition of the names and parameters of the elements can be obtained in the first embodiment, and the details are omitted here.

TABLE 5

TABLE 6

Referring to fig. 7, the left side of fig. 7 shows the light astigmatism diagrams of the optical system 100 in the third embodiment at wavelengths of 623nm, 546nm, 454 nm. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatic curves represent the meridional imaging plane curvature T and the sagittal imaging plane curvature S, and it can be seen from the optical system 100 in fig. 7 that the maximum values of the arc-loss field curvature and the meridional field curvature are both smaller than 0.2mm, at which wavelength the astigmatism of the optical system 100 is well compensated.

The right-hand graph in fig. 7 is a distortion graph of the optical system 100 in the third embodiment at a wavelength of 546 nm. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from the right-hand graph in fig. 7, the maximum distortion is less than 30% at a wavelength of 546nm, and the distortion of the optical system 100 is well corrected.

Fourth embodiment

Referring to fig. 8, in the optical system 100 of the present embodiment, the optical system includes, in order from the projection plane to the image source plane 102 along the optical axis O, a diaphragm 101, a first lens L1 with positive refractive power, a reflective polarizing structure 10, a second lens L2 with negative refractive power, a transflective structure 20, and an optical filter 40. Wherein the reflective polarizing structure 10 is a composite film composed of a linear polarizing film and a polarizing reflective film.

The projection side 11 of the first lens L1 is convex at the paraxial region O, and the image source side 12 of the first lens L1 is convex at the paraxial region O. The projection side 13 of the second lens L2 is convex at the paraxial region O and the image source side 14 of the second lens L2 is convex at the paraxial region O.

In use, after passing through the optical filter 40, the transflective structure 20, the second lens L2 and the reflective polarizing structure 10 in order, the light from the image source surface 102 is screened and deflected on the reflective polarizing structure 10, that is, after polarized light is split and the direction of part of the polarized light is changed by the reflective polarizing structure 10, part of the polarized light is folded back and passes through the second lens L2, and then the polarized light is reflected on the transflective structure 20, so that the polarized light is folded back on the image source side 14 of the second lens L2 and passes through the second lens L2, the reflective polarizing structure 10 and the first lens L1 in order, and finally enters the projection surface.

The parameters of each lens of the optical system 100 in this embodiment are given in table 7, wherein the names and parameters of each element can be defined in the first embodiment, and the description thereof is omitted herein.

TABLE 7

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TABLE 8

Face number

K

A4

A6

A8

A10

A12

S1

0.00000E+00

1.15534E-05

-2.11602E-08

3.14662E-11

-2.01672E-14

0.00000E+00

S2

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S3

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S4

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S5

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S6

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S7

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S8

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S9

6.54336E+01

-1.13491E-06

1.01423E-08

-4.25819E-11

5.52405E-14

-2.74619E-17

S10

0.00000E+00

1.05817E-06

3.72562E-09

-9.53679E-12

5.32644E-15

7.74030E-19

S11

6.54336E+01

-1.13491E-06

1.01423E-08

-4.25819E-11

5.52405E-14

-2.74619E-17

S12

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S13

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S14

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S15

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S16

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S17

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S18

5.34083E+01

1.49693E-06

1.80013E-09

-1.38930E-12

-3.66678E-15

0.00000E+00

S19

6.54336E+01

-1.13491E-06

1.01423E-08

-4.25819E-11

5.52405E-14

-2.74619E-17

S20

0.00000E+00

1.05817E-06

3.72562E-09

-9.53679E-12

5.32644E-15

7.74030E-19

Referring to fig. 9, the left side of fig. 9 shows the light astigmatism diagrams of the optical system 100 in the fourth embodiment at wavelengths of 623nm, 546nm, 454 nm. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatic curves represent the meridional imaging plane curvature T and the sagittal imaging plane curvature S, and it can be seen from the optical system 100 in fig. 9 that the maximum values of the arc-loss field curvature and the meridional field curvature are both smaller than 0.2mm, at which wavelength the astigmatism of the optical system 100 is well compensated.

The right-hand graph in fig. 9 is a distortion graph of the optical system 100 in the fourth embodiment at a wavelength of 546 nm. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from the right-hand graph in fig. 9, the maximum distortion is less than 30% at a wavelength of 546nm, and the distortion of the optical system 100 is well corrected.

It is understood that in other embodiments, the reflective polarizing structure 10 is disposed on the projection side of the first lens L1, and the transflective structure 20 is disposed on the image source side of the first lens L1 or the projection side of the second lens L2.

It is understood that in other embodiments, the reflective polarizing structure 10 is disposed on the image source side of the first lens L1, and the transflective structure 20 is disposed on the projection side of the second lens L2.

Fifth embodiment

Referring to fig. 10, in the optical system 100 of the present embodiment, the optical system includes, in order from the projection plane to the image source plane 102 along the optical axis O, a diaphragm 101, a first lens L1 with positive refractive power, a reflective polarizing structure 10, a second lens L2 with positive refractive power, a third lens L3 with negative refractive power, a transflective structure 20, and an optical filter 40. Wherein the reflective polarizing structure 10 is a composite film composed of a linear polarizing film and a polarizing reflective film.

The projection side 11 of the first lens L1 is convex at the paraxial region O, and the image source side 12 of the first lens L1 is convex at the paraxial region O. The projection side 13 of the second lens L2 is concave at the paraxial region O, the image source side 14 of the second lens L2 is convex at the paraxial region O, the projection side 15 of the third lens L3 is convex at the paraxial region O, and the image source side 16 of the third lens L3 is convex at the paraxial region O.

In use, after passing through the optical filter 40, the semi-transparent and semi-reflective structure 20, the third lens L3, the second lens L2 and the reflective polarizing structure 10 in order, the light from the image source surface 102 is screened and deflected on the reflective polarizing structure 10, that is, after polarized light is split by the reflective polarizing structure 10 and the direction of part of the polarized light is changed, part of the polarized light is folded back and passes through the second lens L2 and the third lens L3, and then the polarized light is reflected on the semi-transparent and semi-reflective structure 20, so that the polarized light is folded back on the image source side 16 of the third lens L3 and passes through the third lens L3, the second lens L2, the reflective polarizing structure 10 and the first lens L1 in order, and finally is emitted into the projection surface.

The parameters of each lens of the optical system 100 in this embodiment are given in table 9, wherein the definition of each element name and parameter can be obtained in the first embodiment, and the description thereof is omitted herein.

TABLE 9

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Table 10

Face number

K

A4

A6

A8

A10

A12

S1

0.00000E+00

8.63570E-06

-1.96005E-08

4.83164E-11

-4.37764E-14

0.00000E+00

S2

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S3

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S4

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S5

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S6

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S7

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S8

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S9

-1.61374E+15

3.97810E-06

-1.42057E-09

-5.31909E-12

-7.53823E-15

0.00000E+00

S10

4.67101E+02

-2.72315E-06

7.55827E-10

4.86901E-12

4.42193E-15

0.00000E+00

S11

9.00935E+01

-4.33433E-06

8.48266E-09

-4.09674E-11

5.92196E-14

-1.65611E-17

S12

0.00000E+00

1.43804E-06

2.57681E-09

-1.00034E-11

4.49933E-15

2.47295E-18

S13

9.00935E+01

-4.33433E-06

8.48266E-09

-4.09674E-11

5.92196E-14

-1.65611E-17

S14

4.67101E+02

-2.72315E-06

7.55827E-10

4.86901E-12

4.42193E-15

0.00000E+00

S15

-1.61374E+15

3.97810E-06

-1.42057E-09

-5.31909E-12

-7.53823E-15

0.00000E+00

S16

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S17

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S18

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S19

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S20

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S21

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S22

-8.80708E+01

6.09388E-07

7.20478E-10

3.80089E-12

-3.10099E-15

0.00000E+00

S23

-1.61374E+15

3.97810E-06

-1.42057E-09

-5.31909E-12

-7.53823E-15

0.00000E+00

S24

4.67101E+02

-2.72315E-06

7.55827E-10

4.86901E-12

4.42193E-15

0.00000E+00

S25

9.00935E+01

-4.33433E-06

8.48266E-09

-4.09674E-11

5.92196E-14

-1.65611E-17

S26

0.00000E+00

1.43804E-06

2.57681E-09

-1.00034E-11

4.49933E-15

2.47295E-18

Referring to fig. 11, the left side of fig. 11 shows the light astigmatism diagrams of the optical system 100 in the fifth embodiment at wavelengths of 623nm, 546nm, 454 nm. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatic curves represent the meridional imaging plane curvature T and the sagittal imaging plane curvature S, and it can be seen from the optical system 100 in fig. 11 that the maximum values of the arc-loss field curvature and the meridional field curvature are both smaller than 0.2mm, at which wavelength the astigmatism of the optical system 100 is well compensated.

The right-hand graph in fig. 11 is a distortion graph of the optical system 100 in the sixth embodiment at a wavelength of 546 nm. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from the right-hand graph in fig. 11, the maximum distortion is less than 30% at a wavelength of 546nm, and the distortion of the optical system 100 is well corrected.

It is understood that in other embodiments, the reflective polarizing structure 10 is disposed on the image source side of the first lens L1, and the transflective structure 20 is disposed on the image source side of the second lens L2, the projection side of the second lens L2, or the projection side of the third lens L3.

It is understood that in other embodiments, the reflective polarizing structure 10 is disposed on the projection side of the first lens L1 or the image source side of the second lens L2 or the projection side of the third lens L2, and the transflective structure 20 is disposed on the image source side of the first lens L1 or the image source side of the second lens L2 or the projection side of the third lens L3 or the image source side of the third lens L3.

Sixth embodiment

Referring to fig. 12, in the optical system 100 of the present embodiment, the optical system includes, in order from the projection plane to the image source plane 102 along the optical axis O, a diaphragm 101, a first lens L1 with positive refractive power, a reflective polarizing structure 10, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a fourth lens L4 with negative refractive power, a transflective structure 20, and an optical filter 40. Wherein the reflective polarizing structure 10 is a composite film composed of a linear polarizing film and a polarizing reflective film.

The projection side 11 of the first lens L1 is convex at the paraxial region O and the image source side 12 of the first lens L1 is concave at the paraxial region O. The projection side 13 of the second lens L2 is concave at the paraxial region O and the image source side 14 of the second lens L2 is concave at the paraxial region O. The projection side 15 of the third lens L3 is concave at the paraxial region O and the image source side 16 of the third lens L3 is convex at the paraxial region O. The projection side 17 of the fourth lens L4 is convex at the paraxial region O and the image source side 18 of the fourth lens L4 is convex at the paraxial region O.

In use, after passing through the optical filter 40, the transflective structure 20, the fourth lens L4, the third lens L3, the second lens L2 and the reflective polarizing structure 10 in order, light from the image source surface 102 is screened and deflected on the reflective polarizing structure 10, that is, after polarized light is split and changed in direction by the reflective polarizing structure 10, part of polarized light is folded back and passes through the second lens L2, the third lens L3 and the fourth lens L4, and then polarized light is reflected on the transflective structure 20, so that polarized light is folded back on the image source side 18 of the fourth lens L4 and passes through the fourth lens L4, the third lens L3, the second lens L2, the reflective polarizing structure 10 and the first lens L1 in order, and finally is emitted into the projection surface.

The parameters of each lens of the optical system 100 in this embodiment are given in table 11, wherein the names and parameters of each element can be defined in the first embodiment, and are not described herein.

TABLE 11

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Table 12

Face number	K	A4	A6	A8	A10
						S1	0.00000E+00	-5.97927E-05	2.19455E-07	-3.24242E-10	2.63990E-15
S2	0.00000E+00	-5.99031E-05	1.61987E-07	-8.84101E-11	-2.59026E-13
						S11	0.00000E+00	1.65111E-05	-1.93531E-08	5.44631E-12	0.00000E+00
S12	0.00000E+00	1.26034E-05	-1.37453E-08	1.66110E-12	0.00000E+00
						S13	0.00000E+00	-9.49832E-06	2.44003E-08	-3.65661E-11	1.73519E-14
S14	0.00000E+00	-1.81734E-06	6.28220E-09	-7.75128E-12	2.72886E-15
						S15	0.00000E+00	-9.49832E-06	2.44003E-08	-3.65661E-11	1.73519E-14
S16	0.00000E+00	1.26034E-05	-1.37453E-08	1.66110E-12	0.00000E+00
						S17	0.00000E+00	1.65111E-05	-1.93531E-08	5.44631E-12	0.00000E+00
S29	0.00000E+00	1.65111E-05	-1.93531E-08	5.44631E-12	0.00000E+00
						S30	0.00000E+00	1.26034E-05	-1.37453E-08	1.66110E-12	0.00000E+00
S31	0.00000E+00	-9.49832E-06	2.44003E-08	-3.65661E-11	1.73519E-14
						S32	0.00000E+00	-1.81734E-06	6.28220E-09	-7.75128E-12	2.72886E-15

Referring to fig. 13, the left side of fig. 13 shows the light astigmatism diagrams of the optical system 100 in the sixth embodiment at wavelengths of 623nm, 546nm, 454 nm. Wherein, the abscissa along the X-axis direction represents focus offset, and the ordinate along the Y-axis direction represents image height in mm. The astigmatic curves represent the meridional imaging plane curvature T and the sagittal imaging plane curvature S, and it can be seen from the optical system 100 in fig. 13 that the maximum values of the arc-loss field curvature and the meridional field curvature are both smaller than 0.2mm, at which wavelength the astigmatism of the optical system 100 is well compensated.

The right-hand graph in fig. 13 is a distortion graph of the optical system 100 in the sixth embodiment at a wavelength of 546 nm. Wherein, the abscissa along the X-axis direction represents distortion, and the ordinate along the Y-axis direction represents image height in mm. As can be seen from the right-hand graph in fig. 13, the maximum distortion is less than 30% at a wavelength of 546nm, and the distortion of the optical system 100 is well corrected.

It is understood that in other embodiments, the reflective polarizing structure 10 is disposed on the projection side of the second lens L2, and the transflective structure 20 is disposed on the image source side of the second lens L2, the projection side of the third lens L3, the image source side of the third lens L3, the projection side of the fourth lens L4, or the image source side of the fourth lens L4.

It is understood that in other embodiments, the reflective polarizing structure 10 is disposed on the image source side of the first lens L1 or the projection side of the second lens L2 or the projection side of the third lens L3 or the projection side of the fourth lens L4, and the transflective structure 20 is disposed on the image source side of the first lens L1 or the image source side of the second lens L2 or the projection side of the third lens L3 or the projection side of the fourth lens L4 or the image source side of the fourth lens L4.

Table 13 shows values of |sag/r|, FOV, dmax/(2×ih), IH/(2×efl), dmax, TTL, TTL/(2×ih), T1, CT1/ET1, CT2/ET2, and EyeBox in the optical systems 100 of the first to sixth embodiments.

TABLE 13

With continued reference to fig. 14, an embodiment of the present application further provides a head-mounted device 200, which includes a housing 201, a display (not shown) and the optical system 100 described above, wherein the display and the optical system 100 are disposed in the housing 201, and the display is disposed on an imaging surface of the optical system 100. Alternatively, the headset 200 may include, but is not limited to, VR glasses, VR and AR glasses, AR helmets, and the like.

Finally, it should be noted that the above embodiments are merely for illustrating the technical solution of the present application and not for limiting, and although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that the technical solution of the present application may be modified or substituted without departing from the spirit and scope of the technical solution of the present application.

Claims (10)

1. The utility model provides an optical system, its characterized in that includes two piece at least lenses, reflection polarization structure, semi-transparent half reflection structure and phase delay ware of locating between projection plane and the image source face, reflection polarization structure with semi-transparent half reflection structure locates the different surfaces of the lens in two piece at least lenses, reflection polarization structure pastes and locates the surface of lens, reflection polarization structure is located semi-transparent half reflection structure with between the projection plane, phase delay ware locates semi-transparent half reflection structure with between the reflection polarization structure, reflection polarization structure pastes the surface of establishing the lens satisfies following relational expression:

0<|sag/R|<0.1；

The sag is a distance from an intersection point of the surface of the lens attached with the reflection polarizing structure and the optical axis to the maximum effective radius of the surface of the lens attached with the reflection polarizing structure, wherein the distance is parallel to the direction of the optical axis, and R is a curvature radius of the surface of the lens attached with the reflection polarizing structure at the optical axis.

2. The optical system of claim 1, wherein the optical system comprises a first lens and a second lens disposed in sequence between a projection plane and an image source plane, wherein the reflective polarizing structure is disposed on the image source side of the first lens or the projection side of the second lens, and wherein the transflective structure is disposed on the image source side of the first lens or the image source side of the second lens or the projection side of the second lens.

3. The optical system according to claim 2, wherein the optical system comprises a first lens, a second lens and a third lens which are sequentially arranged between a projection surface and an image source surface, the reflection polarization structure is arranged on the image source side of the first lens or the projection side of the second lens or the projection side of the third lens, and the half-transparent half-reflection structure is arranged on the image source side of the first lens or the image source side of the second lens or the projection side of the third lens or the image source side of the third lens.

4. The optical system according to claim 1, wherein the optical system comprises a first lens, a second lens, a third lens and a fourth lens which are sequentially arranged between a projection surface and an image source surface, the reflection polarization structure is arranged on the image source side of the first lens, the projection side of the second lens, the projection side of the third lens, the image source side of the third lens, the projection side of the fourth lens, and the semi-transparent and semi-reflective structure is arranged on the image source side of the first lens, the image source side of the second lens, the projection side of the third lens, the image source side of the fourth lens.

5. The optical system of claim 1, wherein the phase retarder is disposed on a light-passing surface of the lens or a light-passing surface of the reflective polarizing structure, and the phase retarder and the transflective structure are disposed on different surfaces.

6. The optical system of claim 5, wherein the phase retarder is disposed in lamination with the reflective polarizing structure on the light passing surface of the lens disposed correspondingly.

7. The optical system of any one of claims 1-6, wherein the optical system satisfies the following conditional expression:

85°<FOV<100°；

wherein FOV is the maximum field angle of the optical system; and/or the optical system satisfies the following relationship:

35mm<Dmax<55mm；

wherein Dmax is the maximum optical effective diameter of a lens of the at least two lenses; and/or the at least two lenses comprise a first lens adjacent to the projection surface, the optical system satisfying the following conditional expression:

10mm<TTL<22mm；

wherein TTL is a distance between a projection side of the first lens and the image source surface of the optical system on an optical axis; and/or the at least two lenses comprise a first lens close to the projection surface, the optical system further comprises a diaphragm arranged between the first lens and the projection surface, and the optical system meets the following conditional expression:

T1≧10mm；

wherein T1 is the distance between the diaphragm and the projection side of the first lens on the optical axis; and/or the optical system satisfies the following conditional expression:

8mm≦EyeBox≦11mm；

wherein, the EyeBox is the eye box of the optical system.

8. The optical system of any one of claims 1-6, wherein the optical system satisfies the following relationship:

1<Dmax/(2*IH)<1.5；

Wherein, in the optical system, the maximum optical effective diameter in the projection side and the image source side of all lenses is Dmax, and IH is the image height corresponding to the maximum field angle of the optical system; and/or the optical system satisfies the following relationship:

1.54<(2*EFL)/IH<5；

wherein EFL is the effective focal length of the optical system; and/or the at least two lenses comprise a first lens adjacent to the projection surface, the optical system satisfying the following conditional expression:

0.4<TTL/(2*IH)<0.7；

wherein TTL is a distance between a projection side of the first lens and the image source plane of the optical system on an optical axis.

9. The optical system of any one of claims 1-6, wherein the at least two lenses comprise a first lens adjacent to the projection surface and a second lens disposed between the first lens and the image source surface, the optical system satisfying the following conditional expression:

1≦CT1/ET1≦2.5；

wherein CT1 is the distance between the projection side of the first lens and the image source side of the first lens on the optical axis, and ET1 is the distance between the maximum optical effective caliber of the first lens and the direction parallel to the optical axis; and/or the optical system satisfies the following conditional expression:

0.6≦CT2/ET2≦2.5；

wherein CT2 is the distance between the projection side of the second lens and the image source side of the second lens on the optical axis, and ET2 is the distance between the maximum optical effective aperture of the second lens and the direction parallel to the optical axis.

10. A head-mounted device comprising a housing, a display, and an optical system according to any one of claims 1 to 9, wherein the display, the optical system are disposed in the housing, and the display is disposed on an imaging surface of the optical system.