摘要:
A polarizing diffraction element having a wavelength selectivity which functions as a polarizing diffraction element at a wavelength λ1, and which does not function as a diffraction grating not depending on incident polarization state and shows high transmittance at a wavelength λ2, and an optical head device employing the element, are provided. The polarizing diffraction element selectively diffracts or transmits incident light having two different wavelengths each containing a first circularly polarized light and a second circularly polarized light having a rotation opposite from the rotation of the first circularly polarized light, depending on wavelength and polarization state of the incident light. Then, a reflective wavelength region for at least the first circularly incident light, does not contain said two incident wavelengths.
摘要:
A polarizing diffraction element having a wavelength selectivity which functions as a polarizing diffraction element at a wavelength λ1, and which does not function as a diffraction grating not depending on incident polarization state and shows high transmittance at a wavelength λ2, and an optical head device employing the element, are provided.The polarizing diffraction element selectively diffracts or transmits incident light having two different wavelengths each containing a first circularly polarized light and a second circularly polarized light having a rotation opposite from the rotation of the first circularly polarized light, depending on wavelength and polarization state of the incident light. Then, a reflective wavelength region for at least the first circularly incident light, does not contain said two incident wavelengths.
摘要:
A projection type display apparatus comprises a light source optical system having an anisotropic luminance distribution, a transparent-scattering type display element for controlling light emitted from the light source optical system and a projection optical system having an aperture which projects the transmitted light, wherein the aperture of the projection optical system is an aperture having a non-circular opening which is disposed in the vicinity of the focal point of the transmitted light of the transparent-scattering type display element.
摘要:
An illumination device for a direct viewing type display element comprising a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating flat set on a first side of a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an a polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on a second side opposite to said light emitting side of the flat light guide in parallel with the light emitting site.
摘要:
An illumination device for a direct viewing type display element comprising a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating flat set on a first side of a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on a second side opposite to said light emitting side of the flat light guide in parallel with the light emitting site.
摘要:
An active matrix liquid crystal display element comprising an active matrix substrate having an active element for each electrode for picture element, a counter electrode substrate provided with a counter electrode and a liquid crystal polymer composite material in which a nematic liquid crystal having a positive dielectric anisotropy is dispersed and held in a polymer matrix, said liquid crystal polymer composite material being held between the active matrix substrate and the counter electrode substrate wherein the refractive index of the polymer matrix substantially agrees with the ordinary refractive index (n.sub.0) of the liquid crystal used, characterized in that the refractive index anisotropy .DELTA.n of the nematic liquid crystal used is 0.18 or higher, and the average particle diameter R(.mu.m) of the liquid crystal dispersed and held in the polymer matrix, the aspect ratio A in average of liquid crystal particles, and the specific dielectric anisotropy .DELTA..epsilon., the elastic constant K33(10.sup.-12 N) and the viscosity .eta. (cSt) of the liquid crystal satisfy the following relations:3(K33/.eta.).sup.0.5 >R/A>0.7(K33/.DELTA..epsilon.).sup.0.5 (1)and1.3
摘要:
An illumination device for a direct viewing type display element comprising a flat light guide; a light source set such that light is incident on a side portion of said flat light guide; a polarized light separating flat set on a first side of a light emitting side of the flat light guide for transmitting a p polarized light component and reflecting at least a portion of an s polarized light component with respect to a light ray substantially having a predetermined direction of incidence; and a light reflecting sheet disposed on a second side opposite to said light emitting side of the flat light guide in parallel with the light emitting site.
摘要:
A liquid crystal color projection display apparatus having a projection light source, a plurality of liquid crystal display elements for separately modulating lights of a plurality of colors from the projection light source and an optical projection system for projecting light to a projection screen, wherein a liquid crystal and polymer composite put between a pair of substrates each equipped with an electrode is used as the liquid crystal display element, in which a liquid crystal material is dispersed and held in a polymer matrix and the refractive index of the polymer matrix substantially agrees with the ordinary light refractive index (n.sub.o) of the liquid crystal material used, a dichroic mirror is used for color splitting or color synthesis and the dependence of dichroic mirror's spectral characteristics upon the state of polarization is decreased. Clear color images of high purity and excellent hue can be obtained. Size and the cost of the liquid crystal display apparatus can be reduced.
摘要:
A transparent-scattering type optical device which includes a transparent-scattering type optical element having a layer of transparent-scattering mode optical material whose light scattering characteristics are changed in response to an external input; at least one prism having a bottom surface which is attached to an end portion of the transparent-scattering type optical element, and where the prism has a longitudinal cross section of a shape which is either triangular or triangular with a top portion cut away. A pair of angles formed by two opposite sides of the prism and the bottom surface are between 65.degree. and 90.degree. inclusive where one of the two angles is not equal to 90.degree.. A light absorbing face is formed from an area of the prism surface defined by portions of the two opposite sides of the prism nearest to the top.
摘要:
A diffraction element having concave/convex-like diffraction gratings in its two surfaces from which at least two separated light beams can be taken in the same direction without changing largely the propagating direction of diffracted light even if the temperature of the operating environment changes. A diffraction grating having a concave/convex shape in cross-section is formed in the incoming-side surface of the transparent substrate and two diffraction gratings of concave/convex shape in cross-section are formed in the outgoing-side surface wherein the grating pitch of the first one is made equal to the grating pitch of one of the second ones.In addition, a reflection type diffraction element exhibiting a good wavelength dependence of diffraction efficiency without being dependent largely on the direction of polarization of an incoming light is provided. A pseudo sawtooth-like diffraction grating is formed in either surface of the transparent substrate, a reflective film is formed on a diffraction grating portion, and an antireflective film is formed on the opposite surface.