CN215813702U - Optical mechanical system, projection equipment and optical path compensation element - Google Patents

Abstract

The application provides an optical-mechanical system, a projection device and an optical path compensation element. The first spatial light modulator of the optical-mechanical system is used for modulating the illumination light emitted by the luminous light source into image light propagating along a first light path and non-image light propagating along a second light path, the image light is sequentially incident to the optical path compensation element, the optical-mechanical relay lens group, the optical-mechanical prism and the second spatial light modulator, the image light has different optical paths in the first transmission part and the second transmission part of the optical machine prism, the optical path compensation quantity of the first optical path compensation part of the optical path compensation element is different from the optical path compensation quantity of the second optical path compensation part, the first optical path compensation part corresponds to the first transmission part, the second optical path compensation part corresponds to the second transmission part, the optical path compensation element can compensate the optical path difference of the image light between the first transmission part and the second transmission part, thereby reducing the field curvature influence of the optical-mechanical prism on the image light, being beneficial to improving the imaging quality of an optical-mechanical system and further improving the effect of projecting pictures of the projection equipment.

Description

Optical mechanical system, projection equipment and optical path compensation element

Technical Field

The application relates to the technical field of projection, in particular to an optical mechanical system, projection equipment and an optical path compensation element.

Background

In the projection scheme of the spatial light modulator, two spatial light modulators are usually used to realize high dynamic display, the first spatial light modulator is used for pre-modulation, and the image light generated by the pre-modulation is incident to the second spatial light modulator for secondary modulation, also called as main modulation. However, the propagation of image light between two spatial light modulators usually requires the cooperation of prisms, and the prisms easily cause the dispersion of the image light, resulting in significant aberration of the system, so that the edges of the area light spots on the spatial light modulators are imaged blurry, and color stripes are formed at the overlapping positions between different areas, which finally affects the effect of the projection picture.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an optical-mechanical system, a projection device and an optical path compensation element to solve the technical problem.

The embodiments of the present application achieve the above object by the following means.

In a first aspect, an optical-mechanical system includes a light-emitting source, a first spatial light modulator, an optical path compensation element, an optical-mechanical relay lens group, an optical-mechanical prism, and a second spatial light modulator. The light emitting source is used for emitting illumination light. The first spatial light modulator is configured to modulate the illumination light into image light propagating along a first optical path and non-image light propagating along a second optical path. The optical path compensation element, the optical machine relay lens group, the optical machine prism and the second spatial light modulator are located on the first optical path, and the image light is sequentially incident to the optical path compensation element, the optical machine relay lens group, the optical machine prism and the second spatial light modulator. The optical machine prism is provided with a first transmission part and a second transmission part, and the image light has different optical paths in the first transmission part and the second transmission part. The optical path compensation element is provided with a first optical path compensation part and a second optical path compensation part, the optical path compensation amount of the first optical path compensation part is different from that of the second optical path compensation part, the first optical path compensation part corresponds to the first transmission part, and the second optical path compensation part corresponds to the second transmission part.

In some embodiments, the optical path length compensation element is an optical path length compensation prism.

In some embodiments, the opto-mechanical system further comprises a light recycling optic set positioned on the second optical path for directing the non-image light to the first spatial light modulator.

In some embodiments, the opto-mechanical system further includes a beam splitter prism for directing the illumination light to the first spatial light modulator, the beam splitter prism further for directing the image light to the optical path length compensation element, the beam splitter prism further for directing the non-image light to the light recycling optic set, the beam splitter prism further for directing the non-image light exiting the received light recycling optic set to the first spatial light modulator.

In some embodiments, the light splitting prism includes a first prism having a first surface, a second surface and a third surface, the first surface transmitting the illumination light, the second surface reflecting the illumination light and transmitting the image light and the non-image light, the third surface transmitting the illumination light, the image light and the non-image light, the first prism for receiving the illumination light through the first surface, reflecting the illumination light from the third surface to the first spatial light modulator through the second surface, and further directing the image light and the non-image light received from the third surface to the second prism through the second surface. The second prism has a fourth surface that transmits image light and reflects non-image light, the second prism for directing image light received from the fourth surface to the third prism and for reflecting non-image light through the fourth surface to the light recovery optic set. The third prism has an image light exit surface for exiting the image light from the image light exit surface and guiding the image light to the optical path compensation element, the image light exit surface being parallel to the third surface.

In some embodiments, the optical path length compensation element and the third prism are integrally formed.

In some embodiments, the opto-mechanical system further includes a polarization beam splitter, the polarization beam splitter being located in an optical path of the outgoing light from the first spatial light modulator, the polarization beam splitter being configured to direct the image light in the P-polarization state to the optical path compensation element, and the polarization beam splitter being further configured to direct the non-image light in the S-polarization state to the light recycling lens group.

In some embodiments, the opto-mechanical system further comprises a light uniformizing device positioned in the optical path of the illumination light for directing the illumination light to the first spatial light modulator; the dodging device is also positioned on a light path of emergent light from the light recovery lens group and is also used for guiding non-image light to the first spatial light modulator.

In some embodiments, the opto-mechanical system further includes a polarization beam splitter and a diffuser, the polarization beam splitter being located in the optical path of the illumination light, the polarization beam splitter being configured to direct the illumination light in the S-polarization state to the first spatial light modulator, the first spatial light modulator being configured to modulate the illumination light in the S-polarization state into image light in the P-polarization state and non-image light in the S-polarization state, the polarization beam splitter being further configured to direct the image light in the P-polarization state to the optical path compensation element, the polarization beam splitter being further configured to direct the non-image light in the S-polarization state to an optical path that is offset from the optical path compensation element.

In some embodiments, the opto-mechanical system further comprises a diffuser, the polarizing beam splitter further configured to direct the non-image light in the S-polarization state to the diffuser, and the diffuser configured to exit the non-image light in the S-polarization state to the polarizing beam splitter.

In some embodiments, the opto-mechanical system further includes a third spatial light modulator, the polarization beam splitter is configured to direct the illumination light in the P-polarization state to the third spatial light modulator, the third spatial light modulator is configured to modulate the illumination light in the P-polarization state into image light in the P-polarization state and non-image light in the S-polarization state, the polarization beam splitter is further configured to direct the image light in the P-polarization state emitted from the third spatial light modulator to the optical path compensation element, and the polarization beam splitter is further configured to direct the non-image light in the S-polarization state emitted from the third spatial light modulator to the diffuser.

In a second aspect, an embodiment of the present application further provides a projection device, where the projection device includes the optical-mechanical system in any of the above embodiments.

In a third aspect, an embodiment of the present application further provides an optical path compensation element applied to an optical-mechanical system, where the optical-mechanical system includes an optical-mechanical relay lens group and an optical-mechanical prism, the optical-mechanical prism has a first transmission portion and a second transmission portion, and light has different optical paths in the first transmission portion and the second transmission portion. The optical path compensation element is provided with a first optical path compensation part and a second optical path compensation part, the optical path compensation amount of the first optical path compensation part is different from that of the second optical path compensation part, the first optical path compensation part corresponds to the first transmission part, the second optical path compensation part corresponds to the second transmission part, and the optical path compensation element is used for guiding the received image light to the prism optical machine through the optical machine relay lens group.

In the optical-mechanical system, the projection device and the optical path compensation element provided by the embodiment of the application, the first spatial light modulator modulates the illumination light of the light-emitting source into the image light which has different optical paths in the first transmission part and the second transmission part of the optical-mechanical prism, the image light forms an inverted image after passing through the optical-mechanical relay lens group, the optical path compensation element is provided with a first optical path compensation part and a second optical path compensation part, the optical path compensation amount of the first optical path compensation part is different from that of the second optical path compensation part, the first optical path compensation part corresponds to the first transmission part, the second optical path compensation part corresponds to the second transmission part, the optical path compensation element can compensate the optical path difference of the image light between the first transmission part and the second transmission part, thereby reducing the field curvature influence of the optical-mechanical prism on the image light, being beneficial to improving the imaging quality of an optical-mechanical system and further improving the effect of projecting pictures of the projection equipment.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 illustrates a schematic structural diagram of an optical-mechanical system according to an embodiment of the present disclosure.

Fig. 2 illustrates a partial structural schematic diagram of the opto-mechanical system of fig. 1.

Fig. 3 illustrates a schematic structural diagram of an optical path compensation element and a beam splitter prism of an optical-mechanical system according to an embodiment of the present disclosure.

Fig. 4 illustrates a schematic structural diagram of a fourth prism of the optical-mechanical system according to an embodiment of the present disclosure.

Fig. 5 is a schematic diagram illustrating arrangement positions of the first spatial light modulator, the optical path length compensation element, and the second spatial light modulator in the optical-mechanical system according to the embodiment of the present disclosure.

Fig. 6 is a schematic diagram illustrating arrangement positions of a first spatial light modulator, an optical path length compensation element, and a second spatial light modulator in an optical-mechanical system according to another embodiment of the present disclosure.

Fig. 7 is a schematic diagram illustrating arrangement positions of a first spatial light modulator, an optical path length compensation element, and a second spatial light modulator in an optical-mechanical system according to still another embodiment of the present disclosure.

Fig. 8 is a schematic diagram illustrating arrangement positions of a first spatial light modulator, an optical path length compensation element, and a second spatial light modulator in an optical-mechanical system according to still another embodiment of the present disclosure.

Fig. 9 is a schematic structural diagram illustrating an opto-mechanical system according to another embodiment of the present disclosure.

Fig. 10 is a schematic structural diagram illustrating an opto-mechanical system according to still another embodiment of the present disclosure.

Fig. 11 is a schematic structural diagram illustrating an optical-mechanical system according to still another embodiment of the present disclosure.

Detailed Description

In order to make the technical solution better understood by those skilled in the art, the technical solution in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It should be apparent that the described embodiments are only some embodiments of the present application, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any inventive step based on the embodiments in the present application, are within the scope of protection of the present application.

In order to reduce the influence of aberration in the related art, a prism is replaced by a wedge-shaped lens to transmit image light between two spatial light modulators, the surface of the lens has a curvature radius, for example, the surface is a convex surface or a concave surface, so that the lens has the function of converging and diverging the light, and the wedge-shaped lens reduces the height difference between the optical axis of incident light and the optical axis of emergent light, so that the emergent angle is reduced, and the aberration of the system is improved. In addition, the related art generally further reduces aberrations by increasing the number of lenses, using aspherical lenses, replacing lens materials, and the like.

In the related art, a prism is also used to reduce aberration, for example, the prism is placed in front of a prism group of a second modulator to reduce coma, and since light passes through the prism and then enters the second modulator through the prism group, an imaging position is shifted around a field of view, and curvature of field cannot be reduced.

Based on this, the embodiment of the application provides a projection device, and the projection device can effectively reduce curvature of field. Referring to fig. 1, the projection apparatus includes an optical-mechanical system 100, and the optical-mechanical system 100 can achieve an effect of projecting a projection image by the projection apparatus.

The optical-mechanical system 100 includes a light-emitting source 10, a first spatial light modulator 20, an optical path compensation element 30, an optical-mechanical relay lens group 40, an optical-mechanical prism 50, and a second spatial light modulator 60.

The light emitting light source 10 is for emitting illumination light. The Light Emitting source 10 may be a Laser Diode (Laser Diode) or a Light Emitting Diode (Light Emitting Diode) or a fluorescent Light Emitting element including a wavelength conversion device. The illumination light emitted by the light emitting source 10 may be laser light, fluorescent light, or other types of light.

The first spatial light modulator 20 is used to modulate the illumination light into image light propagating along a first optical path and non-image light propagating along a second optical path. Here, the image light refers to light for image display after the first spatial light modulator 20 modulates the illumination light according to the image data signal, and the non-image light refers to light for image display after the first spatial light modulator 20 modulates the illumination light. For example, the first spatial light modulator 20 may be a Digital Micromirror Device (DMD), and light emitted from a micromirror of the first spatial light modulator 20 in the "ON" state is image light, and light emitted from a micromirror in the "OFF" state is non-image light. For example, the first spatial light modulator 20 may be a Liquid Crystal Display (LCD), a Liquid Crystal On Silicon (LCOS), or the like.

The optical path compensation element 30, the optical-mechanical relay lens group 40, the optical-mechanical prism 50, and the second spatial light modulator 60 are located in the first optical path, and the image light sequentially enters the optical path compensation element 30, the optical-mechanical relay lens group 40, the optical-mechanical prism 50, and the second spatial light modulator 60, and is finally modulated by the second spatial light modulator 60 and then exits to the outside of the optical-mechanical system 100.

The optical prism 50 has a first transmission part 51 and a second transmission part 52, and the image light has different optical paths in the first transmission part 51 and the second transmission part 52. The size of the optical-mechanical prism 50 may be adjusted to make the image light have different optical paths in the first transmission part 51 and the second transmission part 52, for example, the thickness L1 of the first transmission part 51 may be greater than the thickness L2 of the second transmission part 52, so that the optical path of the image light passing through the first transmission part 51 is longer than the optical path of the image light passing through the second transmission part 52; for another example, the thickness L1 of the first transmission part 51 may be smaller than the thickness L2 of the second transmission part 52, and the optical path length of the image light passing through the first transmission part 51 is shorter than the optical path length of the image light passing through the second transmission part 52. The sizes of the first and second transmissive parts 51 and 52 may also be adjusted according to the type of the projection apparatus. For the convenience of optical path analysis, the optical machine prism 50 'is an equivalent prism symmetrically expanded along one side of the optical machine prism 50 according to the optical machine prism 50, and similarly, the second spatial light modulator 60' is an equivalent modulator of the second spatial light modulator 60 corresponding to the equivalent prism symmetrically expanded along one side of the optical machine prism 50.

The optical path compensation element 30 includes a first optical path compensation unit 31 and a second optical path compensation unit 32, the first optical path compensation unit 31 corresponds to the first transmission unit 51, and the second optical path compensation unit 32 corresponds to the second transmission unit 52. The optical path compensation amount of the first optical path compensation portion 31 is different from that of the second optical path compensation portion 32, for example, the optical path compensation element 30 may adjust the optical path by forming different thicknesses, in some embodiments, the optical path compensation element 30 may adopt an optical path compensation prism, and may also adopt an optical path compensation lens, but in the scenario of solving the field curvature problem, an optical path compensation prism, such as an irregular wedge-shaped prism, is preferably selected.

The optical path compensation amounts of the first optical path compensation unit 31 and the second optical path compensation unit 32 can be adjusted according to the sizes of the first transmission unit 51 and the second transmission unit 52, as shown in fig. 2, since the image light forms an inverted image after passing through the opto-mechanical relay lens group 40, when the thickness L1 of the first transmission unit 51 is smaller than the thickness L2 of the second transmission unit 52, the optical path compensation amount of the first optical path compensation unit 31 can be smaller than the optical path compensation amount of the second optical path compensation unit 32, for example, the thickness L3 of the first optical path compensation unit 31 is smaller than the thickness L4 of the second optical path compensation unit 32. When the thickness L1 of the first transmission part 51 is greater than the thickness L2 of the second transmission part 52, the optical path length compensation amount of the first optical path length compensation part 31 may be greater than the optical path length compensation amount of the second optical path length compensation part 32, for example, the thickness L3 of the first optical path length compensation part 31 is greater than the thickness L4 of the second optical path length compensation part 32. Thus, the optical path compensation element 30 can compensate the optical path difference between the first transmission part 51 and the second transmission part 52 of the image light, thereby reducing the field curvature influence of the optical-mechanical prism 50 on the image light, contributing to improving the imaging quality of the optical-mechanical system 100, and further improving the effect of projecting pictures by the projection device.

Referring to fig. 1, the opto-mechanical system 100 may further include a light recycling lens assembly 70, the light recycling lens assembly 70 may be located on the second optical path, and the light recycling lens assembly 70 may be configured to guide the non-image light to the first spatial light modulator 20. The optical-mechanical system 100 recycles the non-image light, so that the non-image light returns to the light path again, and is at least partially emitted in the form of image light after being modulated again by the first spatial light modulator 20, thereby improving the utilization rate of the light.

The light recycling lens group 70 may include a first reflecting mirror 71, a light recycling relay lens group 72, a second reflecting mirror 73, and a third reflecting mirror 74, where the first reflecting mirror 71, the light recycling relay lens group 72, the second reflecting mirror 73, and the third reflecting mirror 74 may be sequentially located on the second optical path, the first reflecting mirror 71 may guide the received non-image light to the light recycling relay lens group 72, the light recycling relay lens group 72 may guide the non-image light to the second reflecting mirror 73 after converging, and the second reflecting mirror 73 may guide the converged non-image light to the third reflecting mirror 74 and re-enter the first spatial light modulator 20 through the third reflecting mirror 74.

The opto-mechanical system 100 may further comprise an dodging device 80, the dodging device 80 may be located in the optical path of the illumination light, and the dodging device 80 may be configured to direct the illumination light to the first spatial light modulator 20. The light unifying device 80 may also be located in the optical path of the exit light from the light recycling optics group 70, and the light unifying device 80 may also be used to direct the non-image light to the first spatial light modulator 20. Thus, the dodging of the illumination light and the non-image light can be realized by using one dodging device 80, which is beneficial to reducing the number of the dodging devices 80.

The opto-mechanical system 100 may also employ a beam splitter to achieve separation of illumination light, image light, non-image light, etc., and the type of beam splitter may be adjusted according to the types of the first spatial light modulator 20 and the second spatial light modulator 60. For example, when the first spatial light modulator 20 and the second spatial light modulator 60 are both DMD, the optical-mechanical system 100 may further include a beam splitter prism 90, where the beam splitter prism 90 may be configured to guide the illumination light to the first spatial light modulator 20, the beam splitter prism 90 may also be configured to guide the image light to the optical path compensation element 30, the beam splitter prism 90 may also be configured to guide the non-image light to the light recycling lens group 70, and the beam splitter prism 90 may also be configured to guide the non-image light emitted from the received light recycling lens group 70 to the first spatial light modulator 20. In this way, the beam splitter prism 90 can separate illumination light, image light, non-image light, and the like, and efficiently guide different light to different optical paths.

Referring to fig. 2, the beam splitter prism 90 may include a first prism 91, a second prism 92 and a third prism 93, the first prism 91 has a first surface 911, a second surface 912 and a third surface 913, and the first surface 911, the second surface 912 and the third surface 913 may be sequentially connected. The first surface 911 transmits illumination light, the second surface 912 reflects illumination light and transmits image light and non-image light, and the third surface 913 transmits illumination light, image light and non-image light. The first prism 91 is used to receive illumination light through the first surface 911 and reflect the illumination light from the third surface 913 to the first spatial light modulator 20 through the second surface 912, achieving total reflection of the illumination light to the first spatial light modulator 20. The first prism 91 serves to guide the image light and the non-image light received from the third surface 913 to the second prism 92 also through the second surface 912.

The second prism 92 has a fourth surface 921, the fourth surface 921 transmits the image light and reflects the non-image light, the second prism is configured to guide the image light received from the fourth surface 921 to the third prism 93, and is further configured to reflect the non-image light to the light recovery mirror group 70 through the fourth surface 921, and separation of the image light and the non-image light is achieved.

The third prism 93 has an image light emitting surface 931, the third prism 93 is configured to emit the image light from the image light emitting surface 931 and guide the image light to the optical path compensation element 30, and the image light emitting surface 931 may be parallel to the third surface 913, so that the third prism 93 corrects an optical path difference generated by the image light passing through the first prism 91 and the second prism 92, which is beneficial to improving the imaging quality of the optical bench system 100.

The optical path compensation element 30 and the third prism 93 are integrally formed, which helps to simplify the processing difficulty of the optical path compensation element 30 and the third prism 93, and helps to reduce the number of parts of the opto-mechanical system 100. Referring to fig. 3 and 4, the optical path compensation element 30 and the third prism 93 of the integrated structure may be referred to as a fourth prism 94, the fourth prism 94 may be a wedge-shaped prism, for example, the fourth prism 94 may be a regular wedge-shaped prism, and an included angle a between the first edge 943 and the side edge 942 of the light emitting surface 941 of the fourth prism 94₁May be equal to an angle a between the second edge 943 and the side edge 945₂Thereby facilitating the processing of fourth prism 94. For another example, if the fourth prism 94 is an irregular wedge prism, the included angle a between the first edge 943 and the side edge 942 is₁May not be equal to the angle α between the second edge 943 and the side edge 945₂Therefore, the degree of freedom of the structure of the fourth prism 94 is increased, and the variation of the optical path compensation amount of the parts with different thicknesses of the fourth prism 94 is increased, which is beneficial to improving the field curvature correction effect.

In the embodiment of fig. 1, the opto-mechanical system 100 may be applied to the case where both the first spatial light modulator 20 and the second spatial light modulator 60 are DMDs. For example, each of the first spatial light modulator 20 and the second spatial light modulator 60 may be of a type that is flipped around a diagonal line, for example, a type that is flipped around a diagonal line by ± 12 degrees may be used. The illumination light may be obliquely incident to the first spatial light modulator 20 at 45 degrees, for the first spatial light modulator 20, the illumination light, the image light, and the non-image light are in the same plane, the first spatial light modulator 20 is rotated by 45 degrees with respect to the beam splitter prism 90, and the second spatial light modulator 60 is also rotated by 45 degrees with respect to the optical machine prism 50; as shown in fig. 5, the first spatial light modulator 20 and the second spatial light modulator 60 are both tilted by 45 degrees, and there is no tilt angle between the first spatial light modulator 20 and the second spatial light modulator 60. Due to the image inverting function of the optical-mechanical relay lens group 40, the vertex on the first spatial light modulator 20 is imaged below the second spatial light modulator 60, the vertex below the first spatial light modulator 20 is imaged above the second spatial light modulator 60, and due to the action of the optical prism 50, the optical paths corresponding to different object heights on the first spatial light modulator 20 are different, for example when the thickness L1 of the first transmissive part 51 of the opto-mechanical prism 50 may be smaller than the thickness L2 of the second transmissive part 52, the optical path length corresponding to the image light emitted from the upper side of the first spatial light modulator 20 is longer, the optical path length corresponding to the image light emitted from the lower side is shorter, and the optical path length compensating element 30 may compensate for the optical path length difference of the image light, so that the focal points of the image light imaged onto the second spatial light modulator 60 tend to be in the same plane, thereby reducing the curvature of field caused by the optical-mechanical prism 50 and improving the imaging quality of the optical-mechanical system 100.

In addition, as shown in fig. 6, both the first spatial light modulator 20 and the second spatial light modulator 60 can be in a bottom light emitting manner, and the first spatial light modulator 20 and the second spatial light modulator 60 can form a positive corresponding relationship, so that the curvature of field caused by the optical-mechanical prism 50 can be reduced, and the imaging quality of the optical-mechanical system 100 can be improved.

As shown in fig. 7, the first spatial light modulator 20 may be in a bottom light emitting manner, and the second spatial light modulator 60 may be in a side light emitting manner, so that the optical path compensation element 30 may rotate around the Z axis by a certain angle to adapt to the light emitting manner of the first spatial light modulator 20 and the second spatial light modulator 60, and the direction of the optical path compensation element 30 rotating around the Z axis may be the same as the inclination direction of the first spatial light modulator 20, thereby facilitating better reducing field curvature and improving the imaging quality of the optical mechanical system 100.

The opto-mechanical system 100 may also be adapted to the case where the first spatial light modulator 20 and the second spatial light modulator 60 are different models of DMDs. For example, the first spatial light modulator 20 may be of a type that is ± 12 degrees around the diagonal, the second spatial light modulator 60 may be of a type that is ± 17 degrees around both sides, and as shown in the embodiment shown in fig. 8, the optical path length compensation element 30 may be rotated around the Z axis by a certain angle to adapt to the types of the first spatial light modulator 20 and the second spatial light modulator 60, and the direction in which the optical path length compensation element 30 may be rotated around the Z axis may be the same as the direction in which the first spatial light modulator 20 is tilted, thereby helping to reduce the field curvature better.

In the embodiment of fig. 9, the optical-mechanical system 100 may also be applied to a case where the first spatial light modulator 20 is an LCD and the second spatial light modulator 60 is a DMD, and the structure of the optical-mechanical system 100 may be adapted, for example, the optical-mechanical system 100 may further include a polarization beam splitter 96, and the beam splitter prism 90 in the embodiment of fig. 1 may be replaced with the polarization beam splitter 96. A polarizing beam splitter 96 may be located in the optical path of the outgoing light from first spatial light modulator 20, polarizing beam splitter 96 being configured to direct the image light in the P-polarization state to optical path length compensation element 30, and polarizing beam splitter 96 being further configured to direct the non-image light in the S-polarization state to light recovery optics group 70. Thus, the optical path compensation element 30 can compensate the optical path difference between the first transmission part 51 and the second transmission part 52 of the P-polarization image light, so as to reduce the field curvature effect of the optical-mechanical prism 50 on the image light, which is helpful to improve the imaging quality of the optical-mechanical system 100, and further improve the effect of projecting the image by the projection device.

In the embodiment of fig. 10, the optical-mechanical system 100 may also be applied to the case where the first spatial light modulator 20 is an LCOS and the second spatial light modulator 60 is a DMD, and the structure of the optical-mechanical system 100 may be adapted, for example, the optical-mechanical system 100 may further include a polarization beam splitter 96 and a diffuser 97, and the beam splitter prism 90 in the embodiment of fig. 1 may be replaced with the polarization beam splitter 96. A polarization beam splitter 96 may be located in the optical path of the illumination light, the polarization beam splitter 96 being configured to direct the illumination light in the S-polarization state to the first spatial light modulator 20, the first spatial light modulator 20 being configured to modulate the illumination light in the S-polarization state into image light in the P-polarization state and non-image light in the S-polarization state, the polarization beam splitter 96 being further configured to direct the image light in the P-polarization state to the optical path compensation element 30, and the polarization beam splitter 96 being further configured to direct the non-image light in the S-polarization state to the optical path deviating from the optical path compensation element 30. Thus, the optical path compensation element 30 can also compensate the optical path difference between the first transmission part 51 and the second transmission part 52 of the P-polarization image light, so as to reduce the field curvature effect of the optical-mechanical prism 50 on the image light, which is helpful to improve the imaging quality of the optical-mechanical system 100, and further improve the effect of projecting the image by the projection device.

The opto-mechanical system 100 may further include a diffuser 97, the polarization beam splitter 96 is further configured to guide the S-polarization non-image light to the diffuser 97, and the diffuser 97 is configured to emit the S-polarization non-image light to the polarization beam splitter 96. If the light emitted from the light uniformizing device 80 toward the polarizing beam splitter 96 is referred to as a primary light beam, and the light emitted from the polarizing beam splitter 96 toward the light uniformizing device 80 is referred to as a recycled light beam, the diffuser 97 can break the periodicity of the S-polarized non-image light, improve the uniformity of the recycled light, solve the problem of poor imaging effect caused by using the same compound eye to simultaneously homogenize the recycled light and the primary light beam, improve the light utilization efficiency, and also make the display picture of the second spatial light modulator 60 better, thereby effectively improving the user experience.

Referring to fig. 11, in the case where the first spatial light modulator 20 is an LCOS, the second spatial light modulator 60 is a DMD, the opto-mechanical system 100 may further include a third spatial light modulator 98, the third spatial light modulator 98 may be an LCOS, the polarization beam splitter 96 is configured to direct the P-polarized illumination light to the third spatial light modulator 98, the third spatial light modulator 98 is configured to modulate the P-polarized illumination light into a P-polarized image light and an S-polarized non-image light, the polarization beam splitter 96 is further configured to direct the P-polarized image light emitted from the third spatial light modulator 98 to the optical path compensation element 30, the polarization beam splitter 96 is further configured to direct the S-polarized non-image light emitted from the third spatial light modulator 98 to the diffuser 97, and the diffuser 97 is configured to emit the S-polarized non-image light to the polarization beam splitter 96, so that light utilization rate may be improved.

In addition, in the embodiments of fig. 9 to 11, the optical-mechanical system 100 may further include a converging lens 99, the converging lens 99 may be located in an optical path of light emitted from the light uniformizing device 80, the converging lens 99 may converge image light, and the converging lens 99 may also converge non-image light.

Among them, in the embodiment of fig. 10, since the primary light beam is incident from a direction parallel to above the main optical axis of the condensing lens 99 and the recovery light beam is incident from a direction deviated to above the main optical axis of the condensing lens 99, the condensing lens 99 can also realize the spatial separation of the primary light beam and the recovery light beam, and the condensing lens 99 is multiplexed and compact.

In the projection apparatus, the optical-mechanical system 100 and the optical path compensation element 30 provided in the embodiment of the application, the first spatial light modulator 20 modulates the illumination light of the light-emitting source 10 into image light having different optical paths in the first transmission part 51 and the second transmission part 52 of the optical-mechanical prism 50, the image light forms an inverted image after passing through the optical-mechanical relay lens group 40, the optical path compensation element 30 has the first optical path compensation part 31 and the second optical path compensation part 32, the optical path compensation amount of the first optical path compensation part 31 is different from the optical path compensation amount of the second optical path compensation part 32, the first optical path compensation part 31 corresponds to the first transmission part 51, the second optical compensation part 32 corresponds to the second transmission part 52, so that the optical path compensation element 30 can compensate the optical path difference of the image light between the first transmission part 51 and the second transmission part 52, reduce the influence of field curvature caused by the optical-mechanical prism 50 on the image light, and contribute to improving the imaging quality of the optical-mechanical system 100, thereby improving the effect of projecting the picture by the projection equipment.

Furthermore, the terms "first," "second," and the like are used merely for distinguishing between descriptions and not intended to imply or imply a particular structure. The description of the terms "some embodiments," "other embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiments or examples is included in at least one embodiment or example of the utility model. In this application, the schematic representations of the terms used above are not necessarily intended to be the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the various embodiments or examples and features of the various embodiments or examples described in this application can be combined and combined by those skilled in the art without conflicting.

The above embodiments are only for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may be modified or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims (13)

1. An opto-mechanical system, comprising:

a light emitting light source for emitting illumination light;

a first spatial light modulator for modulating the illumination light into image light propagating along a first optical path and non-image light propagating along a second optical path;

the image light sequentially enters the optical path compensation element, the optical-mechanical relay lens group, the optical-mechanical prism and the second spatial light modulator, the optical-mechanical prism is provided with a first transmission part and a second transmission part, and the image light has different optical paths in the first transmission part and the second transmission part; the optical path compensation element is provided with a first optical path compensation part and a second optical path compensation part, the optical path compensation amount of the first optical path compensation part is different from that of the second optical path compensation part, the first optical path compensation part corresponds to the first transmission part, and the second optical path compensation part corresponds to the second transmission part.

2. The opto-mechanical system of claim 1, wherein the optical path compensation element is an optical path compensation prism.

3. The opto-mechanical system of claim 1 further comprising a light recovery lens set positioned on the second optical path for directing the non-image light to the first spatial light modulator.

4. The opto-mechanical system of claim 3 further comprising a beam splitting prism configured to direct the illumination light to the first spatial light modulator, the beam splitting prism further configured to direct the image light to the optical path length compensation element, the beam splitting prism further configured to direct the non-image light to the light recycling optic set, the beam splitting prism further configured to direct the received non-image light exiting the light recycling optic set to the first spatial light modulator.

5. The opto-mechanical system of claim 4, wherein the beam splitting prism comprises a first prism, a second prism, and a third prism;

the first prism has a first surface transmitting the illumination light, a second surface reflecting the illumination light and transmitting the image light and the non-image light, and a third surface transmitting the illumination light, the image light and the non-image light, the first prism is configured to receive the illumination light through the first surface, reflect the illumination light from the third surface to the first spatial light modulator through the second surface, and further guide the image light and the non-image light received from the third surface to the second prism through the second surface;

the second prism has a fourth surface that transmits the image light and reflects the non-image light, the second prism for directing the image light received from the fourth surface to the third prism and for reflecting the non-image light through the fourth surface to the light recovery optic set;

the third prism has an image light exit surface for exiting the image light from the image light exit surface and guiding the image light to the optical path compensation element, the image light exit surface being parallel to the third surface.

6. The opto-mechanical system of claim 5, wherein the optical path compensation element is integrally formed with the third prism.

7. The opto-mechanical system of claim 3 further comprising a polarization splitter positioned in an optical path of the exit light from the first spatial light modulator, the polarization splitter configured to direct the image light in the P polarization state to the optical path compensation element, the polarization splitter further configured to direct the non-image light in the S polarization state to the light recycling optics group.

8. The opto-mechanical system of claim 3 further comprising an dodging device positioned in an optical path of the illumination light, the dodging device configured to direct the illumination light to the first spatial light modulator; the light homogenizing device is also positioned on a light path of emergent light from the light recycling lens group and is also used for guiding the non-image light to the first spatial light modulator.

9. The opto-mechanical system of claim 1 further comprising a polarization beam splitter positioned in an optical path of the illumination light, the polarization beam splitter configured to direct the illumination light in the S-polarization state to the first spatial light modulator, the first spatial light modulator configured to modulate the illumination light in the S-polarization state into the image light in the P-polarization state and the non-image light in the S-polarization state, the polarization beam splitter further configured to direct the image light in the P-polarization state to the optical path compensation element, the polarization beam splitter further configured to direct the non-image light in the S-polarization state to an optical path offset from the optical path compensation element.

10. The opto-mechanical system of claim 9, further comprising a diffuser, the polarizing beam splitter further configured to direct the non-image light in the S-polarization state to the diffuser, the diffuser configured to exit the non-image light in the S-polarization state to the polarizing beam splitter.

11. The opto-mechanical system of claim 10 further comprising a third spatial light modulator, the polarization beam splitter configured to direct the illumination light in the P-polarization state to the third spatial light modulator, the third spatial light modulator configured to modulate the illumination light in the P-polarization state into the image light in the P-polarization state and the non-image light in the S-polarization state, the polarization beam splitter further configured to direct the image light in the P-polarization state exiting from the third spatial light modulator to the optical path compensation element, the polarization beam splitter further configured to direct the non-image light in the S-polarization state exiting from the third spatial light modulator to the diffuser.

12. A projection device comprising the opto-mechanical system of any of claims 1-11.

13. An optical path compensation element applied to an optical-mechanical system is characterized in that the optical-mechanical system comprises an optical-mechanical relay lens group and an optical-mechanical prism, the optical-mechanical prism is provided with a first transmission part and a second transmission part, and light has different optical paths in the first transmission part and the second transmission part;

the optical path compensation element is provided with a first optical path compensation part and a second optical path compensation part, the optical path compensation amount of the first optical path compensation part is different from that of the second optical path compensation part, the first optical path compensation part corresponds to the first transmission part, the second optical path compensation part corresponds to the second transmission part, and the optical path compensation element is used for guiding the received image light to the optical machine prism through the optical machine relay lens group.

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