Abstract: An optical system capable of enhancing a specific polarization state of light beam comprises a polarization beam splitter and a polarization state converter. The polarization beam splitter separates an input light beam into a first light beam of first polarization state and a second light beam of second polarization state. The first polarization state is different from the second polarization state. The second light beam is input into the polarization state converter and converted to a third light beam having significantly much more components of first polarization state. The polarization state converter has a configuration providing total reflection or high reflection function. The configuration includes at least one anisotropic optical thin film that is disposed between an incident medium of high refractive index and a medium of low refractive index.

Abstract: A projection image display apparatus includes: a light source; an illumination optical system that uniformly irradiates a surface of an image modulation element serving as a primary image surface with a light beam emitted from the light source; and a projection optical system that enlarges and projects image information on the primary image surface modulated by the image modulation element onto a screen serving as a secondary image surface, and that includes a first optical system that forms an intermediate image from the image information, a single-image second optical system that enlarges and projects the intermediate image to display a single image on the screen, a plural-image second optical system that enlarges and projects the intermediate image to display plural images on the screen, and an optical path switching mechanism that selectively guides a light beam from the first optical system to the single-image or plural-image second optical system.

Abstract: An optical switch for performing high extinction ratio switching of an optical signal includes a beam polarizing element and one or more optical elements. The optical elements are configured to direct an optical signal along a first or second optical path based on the polarization state of the optical signal as it passes through the optical elements. The optical switch performs high extinction ratio switching of the optical signal by preventing unwanted optical energy from entering an output port by using an absorptive or reflective optical element or by directing the unwanted optical energy along a different optical path.

Abstract: Optical polarizers and optical isolators and systems that incorporate the optical polarizers and isolators are disclosed. In one aspect, an optical isolator includes a Faraday crystal with a first surface and a second surface opposite the first surface, a first one-dimensional sub-wavelength grating disposed on the first surface, and a second one-dimensional sub-wavelength grating disposed on the second surface. The isolator is to receive a first input beam of light on the first grating and output a polarized first output beam of light through the second grating approximately parallel to the first input beam. The isolator is to also receive a second input beam of light on the second grating and output a polarized second output beam of light through the first grating with the second output beam offset from the second input beam.

Abstract: An optical system includes a display panel, an image former, a viewing window, a proximal beam splitter, and a distal beam splitter. The display panel is configured to generate a light pattern. The image former is configured to form a virtual image from the light pattern generated by the display panel. The viewing window is configured to allow outside light in from outside of the optical system. The virtual image and the outside light are viewable along a viewing axis extending through the proximal beam splitter. The distal beam splitter is optically coupled to the display panel and the proximal beam splitter and has a beam-splitting interface in a plane that is parallel to the viewing axis. A camera may also be optically coupled to the distal beam splitter so as to be able to receive a portion of the outside light that is viewable along the viewing axis.

Abstract: There is provided a device for reducing laser speckle comprising: a first transparent substrate; a second transparent substrate; an SBG sandwiched between said substrates; and transparent electrodes applied to said substrates. The first substrate is optically coupled to a laser source. The face of the second substrate in contact with the SBG is configured as an array of prismatic elements.

Abstract: A free-space optical hybrid is provided. The free-space optical hybrid includes a polarizing beam splitter that split the light beams S and L into horizontal polarization light beams Sx, Lx and orthogonal polarization light beams Sy, Ly, respectively, at least one birefringent crystal splits the horizontal polarization light beams Sx, Lx and orthogonal polarization light beams Sy, Ly into light beams Sxo, Sxe, Lxo, Lxe, Syo, Sye, Lyo, Lye, a light combiner that combine the light beams Sxo+Lxo, Sxo?Lxo, Sxe+jLxe, Sxe?jLxe, Syo+Lyo, Syo?Lyo, Sye+jLye, Sye?jLye and output the light beams at ports. The present invention can realize an optical hybrid in free-space by using a birefringent crystal and can split light beams of different polarization statuses in free-space well. The optical hybrid offers a compact structure and good stability.

Abstract: A polarization-separation device includes: a beam splitter that includes a beam-separating surface, on which a light beam that contains a first light beam and a second light beam impinges, wherein polarization direction of the first light beam and polarization direction of the second light beam are perpendicular to each other, and incident angle of the first light beam and incident angle of the second beam vary independently while incident into the beam-separating surface; a first polarizer arranged in an optical path of light beams having transmitted through the beam splitter, and allows the first light beam to transmit therethrough; and a second polarizer arranged in an optical path of light beams reflected from the beam splitter, and allows the second light beam to transmit therethrough.

Abstract: A polarization converting element group for a projection apparatus is disclosed. The polarization converting element group includes a polarization beam splitter and a half wave plate. The polarization beam splitter splits a light beam into a first polarized light beam with a first polarization direction and a second polarized light beam with a second polarization direction. The half wave plate is placed next to the polarization beam splitter and reciprocally moves between the first and second position. At different time points, the half wave plate changes the polarization direction of the first light beam or the second light beam passing therethrough. With this arrangement, the light beam that exits the polarization converting element group will either be a uniform first polarized light with a first polarization direction or a uniform second polarized light with a second polarization direction.

Abstract: Methods, systems, and devices are provided that may facilitate multibeam coherent detection and/or speckle mitigation. For example, some embodiments provide for multiple simultaneous independent speckle realizations in light reflected from an actively illuminated target while also may simultaneously provide reference beams inherently aligned to each speckle. These tools and techniques may facilitate coherent detection of light returned from a target. In some cases, this may provide the basis for substantial speckle mitigation. With the addition of illumination phase or frequency modulation and/or intelligent algorithmic methods, some designs may utilize the multiple speckle returns to actively mitigate speckle noise, and can further be used to separately measure speckle phase to implement interferometric resolution surface tilt measurement and/or surface imaging. These tools and techniques may be utilized for other purposes related to multibeam coherent detection and/or speckle mitigation.

Abstract: A light source switching device for use in a projection system is provided. The light source switching device comprises at least two light guiding devices and at least one phase switching device. The phase switching device is disposed between the two light guiding devices and adapted to be in one of a first status and a second status. When the first light travels into the light source switching device, the phase switching device is capable of being in the first status such that the first light is adapted to emit out from the outlet surface. When the second light travels into the light source switching device, the phase switching device is capable of being in the second status such that the second light is adapted to emit out from the outlet surface. With the switching operation of the phase switching device, the plural lights provided by plural light sources would be selected and uniformized by the light source switching device.

Abstract: A polarization conversion system (PCS) is located in the output light path of a projector. The PCS may include a polarizing beam splitter, a polarization rotating element, a reflecting element, and a polarization switch. Typically, a projector outputs randomly-polarized light. This light is input to the PCS, in which the PCS separates p-polarized light and s-polarized light at the polarizing beam splitter. P-polarized light is directed toward the polarization switch on a first path. The s-polarized light is passed on a second path through the polarization rotating element (e.g., a half-wave plate), thereby transforming it to p-polarized light. A reflecting element directs the transformed polarized light (now p-polarized) along the second path toward the polarization switch. The first and second light paths are ultimately directed toward a projection screen to collectively form a brighter screen image in cinematic applications utilizing polarized light for three-dimensional viewing.

Abstract: A polarization separation device includes a first end surface on which incident light is incident, a polarization separation surface that reflects an s-polarized light component and transmits a p-polarized light component, a second end surface that is arranged to be opposed to the first end surface, converts the p-polarized light component transmitted through the polarization separation surface to the s-polarized light component, and reflects the converted light component to an optical axis direction which is the same as the incident light, a third end surface from which the s-polarized light component reflected by the polarization separation surface without transmitting through the polarization separation surface is output, and a fourth end surface that is arranged to be opposed to the third end surface and from which the s-polarized light component reflected by the second end surface and the polarization separation surface is output.

Abstract: A 3D display is provided comprising at least one light source, a Switchable Bragg Grating device, a microdisplay and a projection lens system. In one embodiment of the invention the SBG device converts the source light into colour sequential illumination and, and provides sequential orthogonally polarized illumination of the microdisplay for each colour. In one embodiment of the invention the first SBG device converts the source light into colour sequential illumination and, and provides sequential first and second sense circularly polarized illumination. The microdisplay is updated with alternating left and right eye perspective images for stereoscopic viewing.

Abstract: An interactive projection device includes a light source configured to emit an input light beam, wherein the light source comprises a visible light emitting device; a first beam splitter configured to split the input light beam into first and second split light beams; a second beam splitter configured to split a scattered light beam received from a surface into third and fourth split light beams; an image forming device configured to produce an image light beam based on the first split light beam and emit the image light beam onto the surface through the first and second splitters, thereby generating a projection image on the surface; and a detector configured to detect the invisible light of the third split light beam, thereby acquiring a scattering image from the surface.

Abstract: Three dimensional projection systems may be single projector or multiple projector systems. These 3D projection systems may include a one or more polarization conversion systems (PCS). Each PCS may be designed for relatively small throw ratios and thus, may be designed to accommodate the small throw ratios. Each PCS may include a polarizing beam splitter, a first optical stack, a reflector and a second quarter wave retarder. The first optical stack may include a rotator, a polarizer, a polarization switch and a first quarter wave retarder. Each PCS may receive light from a respective projector, and the PBS in each PCS may direct the light toward the first optical stacks. The light may be converted to a different polarization state as it passes through the first optical stack. The converted light may then be re-directed by a reflecting element to a second quarter wave retarder. The second quarter wave retarder may convert linearly polarized light to circularly polarized light.

Abstract: A wavelength combining apparatus includes first and second optical devices. The first optical device collects and collimates or focuses light from multiple laser light sources. The second optical device includes multiple nonparallel dichroic surfaces to combine light received from the first optical device.

Abstract: An optical probe for splitting a beam of light into multiple beams. The optical probe may comprise a first polarizing beam splitter having a first polarization axis, a second polarizing beam splitter having a second polarization axis orthogonal to the first polarization axis, a first half wave plate and a second half wave plate, and optionally a first birefringent phase plate, and a second birefringent phase plate. The first half wave plate may be located before first polarizing beam splitter, and the second half wave plate may be located after the first polarizing beam splitter, relative to the propagation of the light beam. The optical probe may further include a lens for collimating the four light beams. A profilometer includes the optical probe for splitting a beam of light into four light beams, and a scanner for traversing the optical probe over a surface of an element to be measured.

Abstract: Provided is an optical apparatus including a polarization separation element for separating an incident light beam into a first polarization component and a second polarization component and outputting the first polarization component and the second polarization component, a polarization conversion unit including a waveplate for converting one of the first polarization component and the second polarization component into the other polarization component, the waveplate being held to a holding metal plate, and a housing for holding the polarization separation element and the polarization conversion unit.

Abstract: An eyepiece includes an eyepiece frame, an in-coupling polarization beam splitter (“PBS”), an end reflector, and an out-coupling PBS. The eyepiece frame defines an air cavity and includes an illumination region for receiving computer generated image (“CGI”) light into the eyepiece frame and a viewing region to be aligned with an eye of a user. The in-coupling PBS is supported within the eyepiece frame at the illumination region to re-direct the CGI light to a forward propagation path extending along the air cavity towards the viewing region. The end reflector is disposed to reflect the CGI light back along a reverse propagation path within the eyepiece frame. The out-coupling PBS is supported at the viewing region to pass the CGI light traveling along the forward propagation path and to redirect the CGI light traveling along the reverse propagation path out of an eye-ward side of the eyepiece frame.

Abstract: The present disclosure relates generally to an optical element, a light projector that includes the optical element, and an image projector that includes the optical element. In particular, the optical element provides an improved uniformity of light by homogenizing the light with lenslet arrays, such as “fly-eye arrays” (FEA). A first FEA is positioned to intercept and converge an unpolarized combined light before the light is converted to a single polarization state, and a second FEA is positioned to intercept and diverge the converted light having a single polarization state.

Abstract: The present disclosure relates generally to an optical element, a light projector that includes the optical element, and an image projector that includes the optical element. In particular, the optical element provides an improved uniformity of light by homogenizing the light with lenslet arrays, such as “fly-eye arrays” (FEA). The FEA is positioned to homogenize an unpolarized combined light before the light is converted to a single polarization state.

Abstract: An optical system includes a display panel, an image former, a viewing window, a proximal beam splitter, and a distal beam splitter. The display panel is configured to generate a light pattern. The image former is configured to form a virtual image from the light pattern generated by the display panel. The viewing window is configured to allow outside light in from outside of the optical system. The virtual image and the outside light are viewable along a viewing axis extending through the proximal beam splitter. The distal beam splitter is optically coupled to the display panel and the proximal beam splitter and has a beam-splitting interface in a plane that is parallel to the viewing axis. A camera may also be optically coupled to the distal beam splitter so as to be able to receive a portion of the outside light that is viewable along the viewing axis.

Abstract: An optical device is configured to perform both switching and attenuation of an optical beam in response to a single control signal. The optical device includes a liquid-crystal-based beam-polarizing element having polarization-conditioning regions that are controlled using a common electrode. The first polarization-conditioning region conditions the polarization of the input beam in order to separate the input beam into a primary component and a residual component. The second and third polarization-conditioning regions change the polarization of the primary component and the residual component, respectively. The primary component is directed to an output port after it has been attenuated based on its polarization state. The residual component, after passing through the third polarization-conditioning region, has its intensity further reduced based on its polarization state.

Abstract: Delay line interferometer designs using combinations of basic optical components that are expected to simplify manufacture and reduce costs while still providing precision optical performance. The main operative components of these designs are polarization beam splitters, birefringent crystals, optical delay components, and waveplates. Temperature controllers may be provided for adjusting the delay of the optical delay components.

Abstract: An eyepiece for a head mounted display includes an illumination module, an end reflector, a viewing region, and a polarization rotator. The illumination module includes an image source for launching computer generated image (“CGI”) light along a forward propagating path. The end reflector is disposed at an opposite end of the eyepiece from the illumination module to reflect the CGI back along a reverse propagation path. The viewing region is disposed between the illumination module and the end reflector. The viewing region includes a polarizing beam splitter (“PBS) and non-polarizing beam splitter (“non-PBS”) disposed between the PBS and the end reflector. The viewing region redirects the CGI light from the reverse propagation path out of an eye-ward side of the eyepiece. The polarization rotator is disposed in the forward and reverse propagation paths of the CGI light between the viewing region and the end reflector.

Abstract: A reflective polarizing plate apparatus includes a reflective polarizing plate that transmits first linearly polarized light and reflects second linearly polarized light polarized in a direction substantially perpendicular to the direction in which the first linearly polarized light is polarized, a holding member that accommodates and holds the reflective polarizing plate, and a first biasing member that biases a glass surface of the reflective polarizing plate accommodated in the holding member.

Abstract: A beam combiner has a first coating on a first side capable of imparting a first polarization rotation, and a second coating on a second side capable of imparting a second polarization rotation. A first beam impinging on the first side passes through the first and second coatings as a first beam component. Second and third beams impinging on the second side partially reflect off the second coating as a second beam component, and partially transmit through the second coating to reflect off the first coating and exit through the second coating as a third beam component. The first, second and third beam components are disposed at selected positions and have respective selected polarizations as a combined beam spot. The positions and polarization of the beams components result in a projected image having increased allowable brightness and/or having reduced speckle.

Abstract: Polarizers and polarizing beam splitter include one or more pairs of axicons that are configured to separate an input beam into a radially polarized component and a tangentially (or azimuthally) polarized component. A second axicon pair can be provided to recombine the tangentially polarized component so as to provide a more uniform beam intensity. The radially polarized component can be reflected or otherwise directed so that one or both the radial and tangential components are available for use.

Abstract: A pulse multiplier includes a polarizing beam splitter, a wave plate, and a set of mirrors. The polarizing beam splitter receives an input laser pulse. The wave plate receives light from the polarized beam splitter and generates a first set of pulses and a second set of pulses. The first set of pulses has a different polarization than the second set of pulses. The polarizing beam splitter, the wave plate, and the set of mirrors create a ring cavity. The polarizing beam splitter transmits the first set of pulses as an output of the pulse multiplier and reflects the second set of pulses into the ring cavity. This pulse multiplier can inexpensively reduce the peak power per pulse while increasing the number of pulses per second with minimal total power loss.

Abstract: A polarization separating element is configured to include a translucent substrate formed of a crystal material having birefringent properties and optically rotatory power and a polarization separating portion formed on the incidence-side surface of the translucent substrate so as to transmit a P-polarized light beam and reflect an S-polarized light beam. A reflecting element that reflects the S-polarized light beam reflected by the polarization separating portion is disposed so as to be separated approximately in parallel to the translucent substrate. A predetermined function is set such that the P-polarized light beam having passed through the polarization separating portion and been incident to the translucent substrate is converted so as to be parallel to the polarization plane of the S-polarized light beam so that the P-polarized light beam is output as the S-polarized light beam.

Abstract: One embodiment contemplates a polarization insensitive optical circuit constructed of an input/output signal separator, such as an optical circulator or a 1×2 or 2×2 coupler or N×M coupler, a polarization sensitive operator, and a polarization rotator reflector. In an alternate embodiment, the invention contemplates a polarization insensitive optical circuit including a polarization rotator reflector, and a polarization sensitive operator which may include, for example, a first polarization rotator, an operator/coupler, and a polarization beam combiner. Preferably, at least one of the components in the optical circuit is constructed integrally from the substrate upon which the optical circuit is based. For examples the polarization rotator and/or polarization sensitive operator may be monolithic.

Abstract: An optical element that has a flat plate shape and includes a light entering surface and a light exiting surface substantially parallel with the light entering surface, the element includes a plurality of translucent members, a plurality of optical multilayer films, a plurality of phase plates, and a plurality of plasma polymerized films. The translucent members, the optical multilayer films, the phase plates, and the plasma polymerized films are provided along the light entering surface and the light exiting surface. The translucent members include a plurality of oblique surfaces oblique to the light entering surface and the light exiting surface. Each of the optical multilayer films is formed on some of the oblique surfaces. The optical multilayer film is either one of a polarization separating film and a reflecting film.

Abstract: The present invention relates to a low pass filter including a wave plate capable of modulating incident light serving as image information such that A-polarized light and B-polarized light orthogonal to the A-polarized light are at an equivalent light quantity level over a visible light region, i.e., a transmittance takes a value close to 50%. According to the low pass filter of the present invention, it is possible to appropriately reduce a moiré phenomenon generated by an image sensor constituting the optical low pass filter including the above-described wave plate, and suppress degradation of an image quality caused by light quantity deflection of a separated light beam, and the low pass filter of the present invention is therefore useful.

Abstract: A polarization conversion element includes: a plurality of light transmitting substrates sequentially bonded at a plurality of inclined planes thereof that form an angle of approximately 45° with respect to a light incident face and a light emitting face being approximately parallel to the light incident face; a retardation plate providing a phase difference to incident polarized light; a polarization separation film separating incident light into two types of polarized light; and an air layer. In the element, the polarization separation film and the air layer are alternately formed along the plurality of inclined planes.

Abstract: A polarization separation device includes a transmissive substrate formed of crystalline material having a birefringent property and an optical rotatory property, and a polarization separation portion that is provided on an incidence-side surface of the transmissive substrate and transmits P-polarized light and reflects S-polarized light. A reflective element, which reflects the S-polarized light reflected by the polarization separation portion, is disposed substantially in parallel with the transmissive substrate. A phase difference plate is disposed at an emission-side of the transmissive substrate.

Abstract: Various superimposing beam controls that can superimpose beams of light with different optical properties are described. In one aspect, a beam control receives a beam of light and outputs one or more beams. Each beam is output in a different polarization state and with different optical properties. Superimposing beam controls can be incorporated in fluorescence microscopy instruments to split a beam of excitation light into one or more beams of excitation light. Each beam of excitation light has a different polarization and is output with different optical properties so that each excitation beam can be used to execute a different microscopy technique.

Abstract: A polarization converting system and a method of manufacturing the same are provided. The polarization converting system includes a polarization splitting unit splitting incident unpolarized light into two orthogonal polarizations and a polarization converting unit converting incident light into specific polarized light. The polarization converting unit has first and second regions that correspond to the polarization splitting unit and are different in a polarization converting extent from each other.

Abstract: An image display apparatus includes an image display element configured to modulate incident light from a light source, a polarization splitting element that has characteristics of transmitting first polarized light and reflecting second polarized light different from the first polarized light and that is configured to synthesize image light from the image display element to be introduced into a projection optical system, and a phase difference plate that is disposed at a side of the projection optical system relative to the polarization splitting element. The phase difference plate has an optic axis in a direction different from a surface normal direction and an in-plane direction of the phase difference plate.

Abstract: An optical switch for performing high extinction ratio switching of an optical signal includes a beam polarizing element and one or more optical elements. The optical elements are configured to direct an optical signal along a first or second optical path based on the polarization state of the optical signal as it passes through the optical elements. The optical switch performs high extinction ratio switching of the optical signal by preventing unwanted optical energy from entering an output port by using an absorptive or reflective optical element or by directing the unwanted optical energy along a different optical path.

Abstract: In accordance with one embodiment of the present disclosure, an optical signal bidirectional transmission system comprises a bi-directional port configured to receive and output optical beams, an input port configured to receive beams and an output port configured to output beams, and only one birefringent crystal. A first beam manipulation system configured to adjust polarization of the beams, and direct the beams from the bi-directional port to the birefringent crystal. A second beam manipulation system configured to adjust polarization of the beams, and direct the beams from the input port to the birefringent crystal. The birefringent crystal is configured to direct the beams received from the first beam manipulation system such that the beams may exit the second beam manipulation system through the output port and direct the beams received from the second beam manipulation system such that the beams may exit the first beam manipulation system through the bi-directional port.

Abstract: Techniques and devices for depolarizing light and producing a variable differential group delays in optical signals. In one implementation, an input optical beam is split into first and second beams with orthogonal polarizations. One or two optical reflectors are then used to cause the first and second optical beams to undergo different optical path lengths before they are recombined into a single output beam. An adjustment mechanism may used implemented to adjust the difference in the optical path lengths of the first and second beams to produce a variable DGD. When the depolarization of light is desired, the difference in the optical path lengths of the first and second beams is set to be greater than the coherence length of the input optical beam.

Abstract: An optical device comprising a region divided into a first division plane running in parallel with a direction of an incident vector of a laser beam entering an incidence place for the laser beam and a second division plane running in parallel with the direction of the incident vector and normal to the first division plane, wherein: provides the laser beam with phase rotation angles differentiated by ? between the regions divided by the first division plane when the laser beam travels in the direction of the incident vector and is linearly polarized in a direction parallel to the first division plane; and also provides the laser beam with phase rotation angles differentiated by ? between the regions divided by the second division plane when the laser beam travels in the direction of the incident vector and is linearly polarized in a direction parallel to the second division plane.

Abstract: An optical probe for splitting a beam of light into multiple beams. The optical probe may comprise a first polarizing beam splitter having a first polarization axis, a second polarizing beam splitter having a second polarization axis orthogonal to the first polarization axis, a first half wave plate and a second half wave plate, and optionally a first birefringent phase plate, and a second birefringent phase plate. The first half wave plate may be located before first polarizing beam splitter, and the second half wave plate may be located after the first polarizing beam splitter, relative to the propagation of the light beam. The optical probe may further include a lens for collimating the four light beams. A profilometer includes the optical probe for splitting a beam of light into four light beams, and a scanner for traversing the optical probe over a surface of an element to be measured.

Abstract: A beam shaping device, consists of a polarization beam splitter interface (PBS interface), four light surfaces and at least one light processing surface, as well as various entities are described. The PBS interface passes light in P polarization and reflects light in S polarization; two of the four light surfaces are light I/O surfaces, and the other two of them are light surfaces for processing (LSFP); the light processing surface is arranged and oriented to retro-reflect, or close to retro-reflect light beam coming from said PBS interface and back it to where it comes from, and, in the meantime, physically rotate the reflected light beam around its propagating direction by 90°, or close to 90°. The invention works for light beam in any polarization status including non-polarized beam.

Abstract: A beam shaping module capable of receiving a polarized beam from a light source is disclosed including a beam splitter for splitting the polarized beam into a first beam and a second beam wherein the polarization directions of the first beam and the second beam are perpendicular to each other, and a beam combiner for shaping and combining the first beam and the second beam, where the beam combiner is configured to reverse the energy distribution pattern of one of the first beam and the second beam.

Abstract: We describe optical techniques for replicating an image to expand the exit pupil of a head-up laser-based image display system. The system includes image replication optics to replicate an image carried by a substantially collimated beam, the image replication optics comprising a pair of substantially planar reflecting optical surfaces defining substantially parallel planes spaced apart in a direction perpendicular to the parallel planes. The system is configured to launch the collimated beam into a region between the parallel planes such that the reflecting optical surfaces waveguide the beam between the surfaces in a plurality of successive reflections at front and rear optical surfaces. The front optical surface is configured to transmit a proportion of the collimated beam when reflecting the beam such that at each reflection of the collimated beam at the front optical surface a replica of the image is output from the image replication optics.

Abstract: A light intensifying device with a polarization conversion function is provided. The light intensifying device includes a transparent mirror, a spectroscope, a reflective mirror, a light wave converter, and an optical fiber. The transparent mirror is aligned with a light source, and receives a light beam from the light source. The spectroscope receives the light beam transmitted from the transparent mirror, reflects a portion of the received light beam to form an S-polarized light beam and transmits the remained portion to form a P-polarized beam. The reflective mirror receives the S-polarized beam and reflects a S-polarized image to the lens module. The light wave converter receives the P-polarized beam, and converts the P-polarized beam to the S-polarized beam. The optical fiber is connected between the light wave converter and the transparent mirror, and transmits the converted S-polarized beam to the transparent mirror.

Abstract: A free-space optical hybrid is provided. The free-space optical hybrid includes a polarizing beam splitter that split the light beams S and L into horizontal polarization light beams Sx, Lx and orthogonal polarization light beams Sy, Ly, respectively, at least one birefringent crystal splits the horizontal polarization light beams Sx, Lx and orthogonal polarization light beams Sy, Ly into light beams Sxo, Sxe, Lxo, Lxe, Syo, Sye, Lyo, Lye, a light combiner that combine the light beams Sxo+Lxo, Sxo?Lxo, Sxe+jLxe, Sxe?jLxe, Syo+Lyo, Syo?Lyo, Sye+jLye, Sye?jLye and output the light beams at ports. The present invention can realize an optical hybrid in free-space by using a birefringent crystal and can split light beams of different polarization statuses in free-space well. The optical hybrid offers a compact structure and good stability.

Abstract: An optical system that projects a real image to a location in free space and includes one or more features located along the optical path that enhance the viewability of the real image. The optical system includes a converging element for converging a portion of source light so as to form the real image. One viewability-enhancing feature is the use of a broadband reflector-polarizer having high transmitting and reflecting efficiencies. Another viewability-enhancing feature is the use of polarizing elements having substantially matched bandwidth responses and/or comprising an achromatic design. An additional viewability-enhancing feature is the use of a wide-view film to increase the viewing angle of the image.