48 results about "Dextrorotatory" patented technology

The invention relates to the technical field of solid-liquid interfaces and liquid drop movement and control, in particular to a method and device for achieving left-right controllable spontaneous rotation of liquid drops based on light induction, and the method comprises the following steps that acid liquid drops containing photoacid are dropwise added to the surface of liquid metal; a light source system is adopted to irradiate liquid drops on one side of the liquid drops, the liquid drops are induced to locally release non-uniform H < + > ions, and interface chemistry is initiated to generate gradient change distribution; the light intensity generated by the light source system promotes the formation of asymmetric tension distribution on the liquid drop and liquid metal interface, and drives the liquid drop to rotate along a preset direction; and by changing the irradiation position, the liquid drops can be switched between left rotation and right rotation. According to the present invention, by using the mechanism of combining the interface Marangoni effect and the light-induced acidity regulation and control, the stable and rapid spinning behavior of the liquid drop can be represented by adjusting the position, the irradiation time and the irradiation intensity of the illumination region, and the rotation direction can be reversibly switched between the left rotation and the right rotation.

The invention discloses a three-dimensional asymmetric photonic crystal laser and a preparation method thereof. An epitaxial structure of the three-dimensional asymmetric photonic crystal laser comprises an N-type electrode, an N-type InP substrate, an N-type Al < x > < 1 > In < 1-x > < 1 > As upper limiting layer, a quantum well active region, a P-type Al < y > < 1 > In < 1-y > < 1 > As electron barrier layer, a P-type Ga < z > < 1 > In < 1-z > < 1 > Asz < 2 > P < 1-z > 2 functional layer, a P-type Al < x > < 2 > In < 1-x > < 2 > As lower limiting layer, a P-type InP connecting layer, a bottom insulating layer and a P-type electrode, wherein a three-dimensional asymmetric photonic crystal is etched on the P-type GaInAsP functional layer, and a chiral characteristic is introduced by destroying the symmetry of the photonic crystal, so that the P-type GaInAsP functional layer vertically emits a single-mode light beam with left-handed or right-handed circular polarization. By designing an asymmetric photonic crystal structure, efficient output of circularly polarized light beams is achieved, polarization selectivity and light beam quality are remarkably improved, and the advantages of low divergence angle and high light beam stability are achieved.

The present application relates to the technical field of organic synthesis, and particularly relates to a method for preparing (+)-crispine A by means of biological enzyme resolution. First, 6,7-dimethoxy-3,4-dihydroisoquinoline-2-oxide is subjected to 1,3-dipolar cycloaddition with allyl alcohol to obtain a first compound; then the first compound is added into a sulfonylation reagent and zinc powder to obtain a racemate second compound through a three-step continuous series reaction of primary alcohol sulfonylation, nitrogen-oxygen bond cleavage and ring formation; then the second compound is mixed with vinyl acetate and biological enzyme, and chiral resolution is carried out under the action of the biological enzyme to obtain a third compound with right-handed optical rotation and a fourth compound with left-handed optical rotation; finally, the third compound is mixed with an alkaline reagent and a sulfonylation reagent, and then secondary alcohol sulfonylation is carried out to obtain a fifth compound with right-handed optical rotation; the fifth compound is mixed with a deoxidizing reagent to carry out deoxidation reaction, and (+)-crispine A is prepared. The method is simple, green and environmentally friendly, and can be produced in large quantities.

The invention provides an optical mixer based on metasurface integration and a preparation method thereof, and belongs to the field of mixers. The mixer comprises a circularly polarized light beam splitter which comprises a first substrate, a liquid crystal structure, a second substrate and a nanorod array which are stacked in sequence; the nanorod array is used for separating the signal light and the local oscillation light into signal light left-handed rotation light, signal light right-handed rotation light, local oscillation light left-handed rotation light and local oscillation light right-handed rotation light; the liquid crystal structure is used for regulating and controlling the initial phases of the output left-handed light and right-handed light; the first multimode interference coupler is used for receiving and mixing the signal light left-rotation light output by the circularly polarized light beam splitter with the local oscillation light left-rotation light to obtain four paths of left-rotation polarized light components with different phases; and the second multimode interference coupler is used for receiving and mixing the right-handed light of the signal light output by the circularly polarized light beam splitter with the right-handed light of the local oscillation light to obtain four paths of right-handed polarized light components with different phases.

This invention discloses an α-indolylpyrrolo[1,2-a]indole derivative and its preparation method. The derivative is a levorotatory or dextrorotatory optically active form or racemate with the following structural formula: The preparation involves using α-indolylpropynyl alcohols and indole compounds as raw materials, and 3,5-bis(trifluoromethyl)phenylbinaphthylphosphonic acid as a catalyst, reacting in an organic solvent to obtain the α-indolylpyrrolo[1,2-a]indole derivative. This invention utilizes an organophosphate-catalyzed tandem reaction of two components to synthesize the α-indolylpyrrolo[1,2-a]indole derivative. The reaction conditions are mild, the process is simple, and the operation is convenient. The obtained product is the core skeleton of the indole bases of the natural products isoborreverine and dimethyl isoborreverine, which is of great significance for the synthesis of analogs of these natural products.

The invention discloses a preparation method and application of a double-layer composite film with circularly polarized light (CPL) characteristics, and belongs to the technical field of optical materials. According to the invention, a double-layer composite film for finely dividing an optical functional area is designed, a micron-sized fluorescent material is deposited on the bottom layer of the film and is only used for photoluminescence, and cellulose nanocrystals (CNC) are compounded above the fluorescent layer and are only used as an optical filter for selectively transmitting right-handed circularly polarized fluorescence; by controlling the volume of the CNC solution, a thin film with a high asymmetry factor (Glum) and an adjustable Glum factor is obtained. The preparation method breaks through the size limitation that only nanoscale fluorescent powder can be blended with CNC (computer numerical control) to obtain circularly polarized light fluorescent powder in the prior art, greatly expands the selection range of optical inactive materials for obtaining circularly polarized light, is simple and convenient to prepare and operate, is green and environment-friendly, is beneficial to actual production, and is expected to promote the progress of optical anti-counterfeiting.

The application relates to a preparation method and application of chiral two-dimensional cadmium sulfide nanosheets. The application aims to solve the problem that it is difficult to construct non-layered chiral two-dimensional inorganic nanomaterials. The method comprises the following steps: placing a first open reaction container and a second open reaction container in a sealable container, adding a cadmium acetate solution into the first open reaction container, then adding a left-rotational ibuprofen / chloroform solution drop by drop, adding a sodium sulfide aqueous solution into the second open reaction container, then adding a hydrochloric acid solution drop by drop, and finally sealing and standing. The application is used for preparing a circularly polarized light detection device for detecting left-rotational / right-rotational circularly polarized light. The application is used for the preparation and application of chiral two-dimensional cadmium sulfide nanosheets.

A microdrone is adapted to, selectively under illumination, trap and transport a particle. The microdrone comprises a plurality of motion-promoting antenna structures and a trapping-field-promoting antenna structure. The plurality of motion-promoting antenna structures comprises a first motion-promoting antenna structure and a second motion-promoting antenna structure. Each of the first and the second motion-promoting antenna structures exhibits a respective optically addressable resonance at a respective first resonance wavelength. Each of the first and the second motion-promoting antenna structures is adapted to scatter incoming, circularly polarized light at the respective first resonance wavelength such that at least a fraction of a momentum of the incoming, circularly polarized light is transferred to the microdrone. The trapping-field-promoting antenna structure exhibits an optically addressable resonance at a second resonance wavelength. The trapping-field-promoting antenna structure is adapted to provide, under illumination with incoming light at the second wavelength, a gradient force directed at the trapping-field promoting antenna structure both for left-handed circularly polarized incoming light at the second wavelength and for right-handed circularly polarized incoming light at the second wavelength.

The invention relates to a galvanometer type laser fuze discrimination method and system for circular polarization rotation coding. The system comprises a laser, a circular polarization encoder, a micro galvanometer module, a light splitting module, a polarization filtering module, a photoelectric detector and a decoding discrimination module. The micro galvanometer module comprises an MEMS galvanometer A, a rotating shaft and an MEMS galvanometer B; the polarization filtering module comprises a left-hand circular polarization filter A and a right-hand circular polarization filter B; according to the invention, double coding of circular polarization and time is carried out at the laser incident end, so that strong marking of incident signals is realized, and the problem of range ambiguity during long-distance laser ranging can be effectively solved; and an orthogonal rotation circular polarization decoding discrimination method is adopted at the emergent end, so that the influence of back scattering light can be inhibited, the signal-to-noise ratio of the system is further improved, and the method is particularly suitable for discrimination of target reflection signals in a nitrate smoke environment and a heavy fog special environment.

This invention discloses a chiral gold-silver-platinum alloy nanomaterial, its preparation method, and its applications, relating to the field of metal nanomaterials technology. The invention includes: a substrate, wherein the substrate is chiral helical gold-silver alloy nanoparticles, and the substrate has a left-handed or right-handed helical morphology; and platinum nanoparticles, wherein the platinum nanoparticles are selectively deposited on the helical edges of the substrate by photodeposition, and the chiral helical morphology of the substrate is preserved after deposition. The photodeposition method is a photodeposition reaction performed under circularly polarized light irradiation with a specific helical direction. This invention provides more active sites for catalytic reactions and effectively avoids the displacement etching of the gold-silver alloy shell by platinum in traditional deposition methods, preserving the complete helical chiral structure.

This invention relates to a polarization-customized holographic device based on a spin-decoupled plasmonic metasurface, belonging to the fields of micro-nano optics, diffraction optics, and holographic imaging. The device employs a three-layer metal-dielectric-metal reflective structure, consisting of a bottom metal reflective surface, an intermediate dielectric spacer layer, and a top anisotropic metaatomic layer. The top metaatomic layer is composed of various periodically arranged metaatoms. By superimposing the propagation phase and geometric phase, phase decoupling between left-handed circular polarization (LCP) and right-handed circular polarization (RCP) is achieved, allowing independent control of their phase delays. Precise customization of the output linear polarization direction is achieved by adjusting the phase difference between the two. This invention breaks the lock-in relationship between geometric phase and spin state in existing metasurface holographic devices, achieving highly integrated, high-quality polarization-customized holographic imaging. It exhibits stable performance over a wide spectral range and large incident angles, and can be widely applied in optical encryption, secure displays, and optical communications.

The application provides a visible band photonic spin Hall device based on a plasmonic metasurface, which comprises: an anisotropic metasurface, which is designed based on a PB geometric phase principle and is formed by periodic arrangement of supercells; the supercells are arranged by homochiral superatoms every interval p and rotation angle by turns, so that the last superatom of each supercell rotates 180 DEG relative to the first superatom; the superatom is a half-wave plate working in a wide frequency visible light band, that is, when left-handed or right-handed circularly polarized light is incident on the superatom, the reflected light is converted into right-handed or left-handed circularly polarized light; under parallel circularly polarized light incidence, the reflected circularly polarized light of the metasurface device follows the generalized Snell law, and left-handed light and right-handed light are reflected towards opposite directions respectively, that is, a photonic spin Hall effect is generated.

This invention discloses a spin-correlated metalens and a classification system including it. The metalens comprises a substrate and nanostructure units on top of it. The nanostructure units include nanopillars A and B, which are arranged alternately in a square lattice. Incident light passes through the metalens to obtain left-handed and right-handed circularly polarized outgoing light. Nanopillars A and B introduce propagation phase delay through their structural dimensions and geometric phase through rotation angles, respectively, thereby jointly achieving independent amplitude and phase modulation of left-handed and right-handed circularly polarized light. This invention, by combining spin-correlated metalens with polarization phase-shift interference reconstruction, overcomes the physical limitations caused by the loss of point spread function phase information under incoherent imaging conditions. It realizes incoherent optical loading and convolution calculation of arbitrary signed, trainable convolution kernels in the intensity domain, fundamentally solving the problem that traditional incoherent optical systems cannot perform positive and negative weighted convolution.

The invention discloses a chiral metasurface construction method based on rotation transformation, a metasurface device comprises a substrate and a chiral metasurface located on the substrate, and the chiral metasurface is a rectangular nanorod array arranged periodically. The metasurface unit is composed of rotating rectangular silicon nanorods, and selective regulation and control of spin angular momentum of incident light are achieved by introducing in-plane mirror symmetry of a geometric rotation destroying structure. Simulation results show that the metasurface shows remarkable circular dichroism at the resonant wavelength of 633 nm, the transmissivity of the metasurface to left-hand circularly polarized light reaches up to 73%, and meanwhile the transmissivity of right-hand circularly polarized light is restrained to 2%. The device has the advantages of compact structure, easiness in integration and the like, and is expected to provide an effective solution for chiral biosensing application.

The application discloses a circularly polarized spectrometer and a spectral analysis method thereof, and relates to the technical field of circularly polarized spectrum analysis. The chiral structure layer of the circularly polarized photodetector of the circularly polarized spectrometer comprises a left-handed chiral structure array and a right-handed chiral structure array which are independent and mirror-symmetric; the photosensitive layer comprises a first photosensitive unit and a second photosensitive unit; the first photosensitive unit is electrically connected with a first signal detection module through a first electrode group; the second photosensitive unit is electrically connected with a second signal detection module through a second electrode group; the circularly polarized photodetector is used for collecting left-handed response current and right-handed response current signals under monochromatic light of the same wavelength; and the circularly polarized spectrometer is used for calculating left-handed circularly polarized light intensity and right-handed circularly polarized light intensity according to a formula. The circularly polarized spectrometer can synchronously and quantitatively separate left-handed and right-handed circularly polarized light intensity at a monochromatic wavelength point, and has high device stability and process compatibility.

This application discloses a polarization-independent chiral selective reflection and multidimensional optical field modulation device and method, relating to the fields of integrated photonics and micro / nano optics. The device includes: a geometrically phased liquid crystal layer, a transparent capping layer, a chiral metasurface array layer, a dielectric substrate layer, and a total reflection layer; wherein, the chiral metasurface array layer can break the in-plane mirror symmetry and exhibit chiral selective reflection characteristics in the target wavelength band. The geometrically phased liquid crystal converts the polarization state of arbitrary incident light into orthogonal left-handed and right-handed circularly polarized light. The chiral metasurface array layer selectively reflects one type of circularly polarized light while absorbing another type of circularly polarized light with the opposite chirality. The reflected circularly polarized light exits through the geometrically phased liquid crystal, achieving two-way phase modulation. This invention achieves geometrically phase modulation by four times the rotation angle of liquid crystal molecules, and has the advantages of compact structure, low crosstalk, low cost, and easy integration with semiconductor processes.

The preparation method comprises the following specific steps: S1, weighing L-borneol crystal substances, D-borneol crystal substances and Baijiu, and mixing the L-borneol crystal substances, the D-borneol crystal substances and the Baijiu; s2, putting the mixture into a pressure cooker filled with distilled water, heating the interior of the pressure cooker to a boiling state of 100-105 DEG C by using big fire, and continuously cooking for 4-8 hours by using small fire; and S3, carrying out cooling crystallization treatment to obtain the racemic borneol.

The application provides a linear optical chiral structure generalized composite phase super-structure design method, which comprises the following steps: 1, designing a super-structure device; the super-structure device comprises a metal reflection layer and a metal structure layer stacked from bottom to top, wherein the metal structure layer comprises a chiral metal unit structure with n-fold rotational symmetry; the chiral metal unit structure comprises three circular arc arms, and each circular arc arm comprises a cuboid and a circular arc; 2, when left-handed circularly polarized LCP light is incident, a phase distribution of Φ LCP =+2nθ is generated, wherein θ is a directional angle of a sub-wavelength structure; and when right-handed circularly polarized LCP light is incident, a phase distribution of Φ RCP =-2nθ+β A is generated, wherein β A is an Aharonov-Bohm AA phase; and 3, by adjusting the circular arc length and the rotation angle θ of the chiral structure, left-handed and right-handed circularly polarized light can be independently controlled. The application can preferably realize independent control of circularly polarized light.

The application discloses a circularly polarized light detector and a preparation method thereof, and belongs to the technical field of photoelectric detectors. The circularly polarized light detector comprises, from bottom to top, a substrate, a gate electrode, a conjugated polymer layer, a chiral supramolecular layer, a source electrode and a drain electrode. Thus, the integration degree can be greatly improved, and the overall volume can be reduced to below 10 cm3. The application is suitable for application fields, such as miniature endoscopes and wearable sensors, which have strict requirements on the size of devices, avoids the integration bottleneck caused by the combination of traditional optical elements, has excellent coupling effect on circularly polarized light through the chiral supramolecular layer, can accurately distinguish left-handed and right-handed circularly polarized light, and has a significantly higher asymmetric factor than an organic circularly polarized light detector based on a traditional chiral small molecule or polymer.

This invention discloses a birefringent lens based on metamaterial lenses. By designing a C-shaped slit at the bottom layer and a C-shaped slit at the top layer with different rotation angles δ, the transmitted electromagnetic wave generates a focused right-handed circularly polarized wave and a divergent left-handed circularly polarized wave that propagate along different paths after a linearly polarized wave is incident on the birefringent lens along the positive z-axis. This achieves the dual functions of focusing and diverging of the lens.

The application discloses a turntable type coherent laser communication system with polarization compensation and a compensation method. The device is composed of a laser light source, a collimating mirror, a polarization beam splitter, a rear optical path, a half-wave plate, a quarter-wave plate, a through-axis optical path and a telescope system. The light emitted by the laser light source is collimated by the collimating mirror and is polarized into horizontal polarized light by the polarization beam splitter. The horizontal polarized light passes through the rear optical path, is modulated by the half-wave plate and the quarter-wave plate, passes through the through-axis optical path and is emitted by the telescope system. The half-wave plate and the quarter-wave plate modulate the horizontal polarized light generated by the polarization beam splitter into right circular polarized light and compensate for the additional phase delay and the rotation of the polarization base of each optical path. The phase delay of the rear optical path, the through-axis optical path and the telescope system is measured before loading, and the rotation of the polarization base is obtained in real time according to the attitudes of the azimuth axis and the pitch axis. The compensation angle of the half-wave plate and the quarter-wave plate is calculated and obtained based on the matrix corresponding to the above parameters and through the Mueller-Stokes algorithm.

The invention discloses a broadband full-Stokes parameter measurer based on a liquid crystal two-dimensional polarization grating, and belongs to the technical field of liquid crystal photonics. The problems that an existing polarization measurer is complex in preparation, large in system and limited in narrow band are solved. The liquid crystal display panel comprises two light-transmitting conductive substrates which are oppositely arranged, the opposite surfaces of the substrates are spin-coated with photosensitive orientation layers, interval microspheres are arranged between the two substrates to control the thickness of a box and form a liquid crystal box, and the box is filled with liquid crystal materials; the photosensitive orientation layer is oriented through single holographic exposure, liquid crystal molecules are guided to form a two-dimensional polarization grating, the grating serves as a geometric phase device to work under a half-wave condition, and incident light can be separated into six polarization states including 0-degree / 90-degree linearly polarized light, 45-degree / 135-degree linearly polarized light and right-hand / left-hand circularly polarized light. By measuring the light intensity of six polarization states, the full Stokes parameter of incident light can be obtained at a time, the effective birefringence of the liquid crystal is regulated and controlled by means of voltage, the liquid crystal is adaptive to 450-1550 nm visible light, near-infrared and infrared bands, and the liquid crystal has the advantages of being simple in preparation, easy to integrate and accurate and efficient in measurement.

The invention discloses a system and a method for generating Poynting vector optical skyrmion based on tightly focused second-order circularly polarized vortex light, and belongs to the technical field of light field regulation and control. The method comprises the following steps: firstly, converting incident light into left-handed or right-handed circularly polarized light through a polaroid and a 1 / 4 wave plate, and then loading a specific topological charge value for the left-handed or right-handed circularly polarized light by using a spiral phase modulator; the tight focusing optical unit is continuously used for tight focusing, and the Poynting vector optical Skyrmion is preliminarily generated; then annular amplitude shaping is carried out on the light field through an annular amplitude modulator, and according to the Richards-Wolf vector diffraction theory, it is calculated that the stable and efficient Poynting vector optical Skyrmion tubular structure can be generated in a three-dimensional free space in a focusing field after second-order circular polarization vortex light passes through a tight focusing optical unit. The optical skyrmion topological characteristics and spatial form are controlled by regulating and controlling polarization, phase, amplitude and focusing conditions of the light field.

The application discloses a dark-field thermal wave confocal microscopic measuring device based on circular dichroism, which comprises the following steps: a time division multiplexing circular polarized light generating light path alternately generates left-handed circular polarized light and right-handed circular polarized light in the same period as thermal wave detection light; a thermal wave detection light shaping light path shapes the thermal wave detection light; a thermal wave pump light generating light path generates thermal wave pump light, and after the thermal wave pump light is modulated, the thermal wave pump light is combined with received thermal wave detection light to obtain combined light; a light beam illumination light path irradiates the combined light to a sample to be measured, and receives thermal wave reflection and scattering light; a dark-field balanced detection light path receives the shaped thermal wave detection light, extracts the scattering light of the thermal wave detection light in the thermal wave reflection and scattering light, and obtains a circular dichroism thermal wave dark-field signal according to the difference frequency signal between the reference light and the scattering light of the thermal wave detection light. The application can obtain the chiral information of various physical properties and micro-nano structures of sample defects.

The invention discloses a photo-thermal driven nano-particle directional transmission and double-potential-well capturing method and device based on a chiral plasmon structure, and belongs to the technical field of micro-nano photonics and microfluidic control. The invention aims to solve the problems that in the prior art, directional transmission of nano-particles between spatially separated double potential wells is difficult to realize by adjusting light polarization, and the capture stability is insufficient. The method comprises the following steps: providing a plasmon structure with geometric chirality; placing the nanoparticles in the fluid over the structure; the structure is selectively irradiated by left-handed or right-handed circularly polarized light, and the nanoparticles are driven to directionally migrate between two spatially separated capture potential wells by utilizing light force and thermophoresis force jointly generated by an excited, spatially asymmetric and polarization-dependent local electromagnetic field and a temperature field; by switching the circular polarization chirality of the incident light, the migration direction and the final capture position of the particles are reversibly changed. The device comprises a substrate, a dielectric layer, an embedded chiral structure and a fluid layer which are used for implementing the method.

The invention discloses a broadband spin splitting light field generation method and device based on magneto-optical super atoms and a dipole source, a program and a storage medium, and belongs to the field of micro-nano photonics. The method comprises the following steps: establishing a space rectangular coordinate system; a dipole source is used for exciting magneto-optical super atoms in a wide frequency band to generate an electric dipole moment and a magnetic dipole moment; when the magnetic dipole moment meets the spin splitting condition, an equivalent circular polarization spin dipole source is formed, and a spin splitting light field with left-handed and right-handed circularly polarized light space reverse separation is generated in a far field through spin locking scattering; and the stability in the broadband is verified through normalized Stokes parameters. The limitation that spin splitting can only be achieved at a single frequency point in a traditional scheme is overcome, a stable and pure spin splitting light field in a wide frequency band is achieved through a simple structure, and the device has the advantages of being wide in frequency band and easy to integrate and can be applied to the fields of nanometer optical sensing, polarization precision measurement, spin-dependent photonic devices and the like.

The invention discloses a passive laser gyroscope based on four-frequency differential motion and a measurement method thereof, and belongs to the technical field of laser gyroscopes. A laser beam splitting module outputs first laser and second laser; the first light beam locking module and the second light beam locking module carry out frequency locking, and inject the first path of laser into the annular resonant cavity module in the anticlockwise direction and inject the second path of laser into the annular resonant cavity module in the clockwise direction; the annular resonant cavity module carries out reciprocal frequency splitting and non-reciprocal frequency splitting to form clockwise left-handed polarized light, clockwise right-handed polarized light, anticlockwise left-handed polarized light and anticlockwise right-handed polarized light with different frequencies, so that a first path of optical signal and a second path of optical signal are formed; and the signal detection module performs signal conversion and differential processing based on the signal detection module to obtain the angular velocity of the resonant cavity. According to the passive laser gyroscope based on the four-frequency differential motion and the measurement method thereof disclosed by the invention, noise related to a gain medium is eliminated, and the stability of high-precision angular velocity measurement is effectively improved.

PROBLEM: To expand a separation angle while maintaining high diffraction efficiency in a polarizing grating. SOLUTION: In this polarization separation element, a plurality of wavelength plates 401, 402 having an optical axis on an xy plane are arranged in the z-axis direction in a three-dimensional space x, y, z, and each of the wavelength plates 401, 402 has a plurality of regions repeated in the x-axis direction, with each region being divided into a plurality of belt-like sub-regions in the x-axis direction. The direction of the optical axis of the odd-numbered wavelength plate 401 changes stepwise in one direction in a range in which the angle with respect to the y-axis direction is from 0° to 180° in the region. The direction of the optical axis of the even-numbered wavelength plate 402 changes stepwise in the direction opposite to the one direction in a range in which the angle with respect to the y-axis direction is from 0° to 180° in the region. The polarization separation element expands, by the number of the wavelength plates, the angle at which a clockwise circularly polarized light component and a counterclockwise circularly polarized light component incident in the z-axis or obliquely incident from the z-axis direction or are separated.