摘要:
An optical system and method for providing a visible light beam with a desired characteristic includes a visible light source producing a visible light beam defining an optical train. An optical element is disposed in the optical train to create a modified beam, and that is capable of introducing an undesired characteristic that continuously transitions across at least a portion of the modified beam. A wire-grid polarizer is disposed in the optical train, and has a plurality of elongated elements with at least a portion that continuously transitions to a different characteristic. The wire-grid polarizer is positioned and oriented in the optical train with the different characteristic corresponding to the undesired characteristic of the modified beam to obtain a visible light beam with a desired characteristic substantially across the visible light beam.
摘要:
A folded projection display system includes a wire-grid polarizer placed immediately behind the system's imaging screen. The display system includes an image projector that projects an image beam containing light of a predetermined linear polarization toward the imaging screen. The wire-grid polarizer reflects the light in the image beam away from the screen. The reflected image beam then encounters a ¼-wavelength achromatic retarder that converts the linear polarization to circular polarization. The image beam next hits a mirror that reflects the light back through the ¼-wavelength achromatic retarder, which converts the circular polarization back to linear polarization, with the polarization director rotated 90 degrees from the original polarization direction. The wire-grid polarizer then allows the light to pass through to the image screen.
摘要:
An optical data storage system includes a laser diode to produce at least one light beam. An inorganic, dielectric grid polarizing beam splitter is disposable in the light beam to transmit a polarized light beam, and includes a stack of film layers disposed over a substrate. Each film layer is formed of a material that is both inorganic and dielectric. Adjacent film layers have different refractive indices. At least one of the film layers is discontinuous to form a form birefringent layer with an array of parallel ribs with a pitch of less than 390 nm. A drive carries a disc medium disposed in the polarized light beam to reflect a modified light beam. The grid polarizer is disposable in the modified light beam to separate the modified light beam into a reflected beam and a transmitted beam. A photo-detector is disposable in the reflected or transmitted beam.
摘要:
A wire grid polarizing beam splitter has a generally parallel arrangement of thin, elongated elements which interact with electromagnetic waves of a source light beam to generally transmit or pass light of one polarization, and reflect light of the other polarization. The arrangement of elements has a throughput greater than approximately 50%, and an extinction greater than approximately 100. In addition, the arrangement of elements has a period less than approximately 0.21 &mgr;m, and a width to period ratio of between approximately 0.25 to 0.76. The elements have a thickness of between approximately 0.05 to 0.5 &mgr;m.
摘要:
A folded projection display system includes a wire-grid polarizer placed immediately behind the system's imaging screen. The display system includes an image projector that projects an image beam containing light of a predetermined linear polarization toward the imaging screen. The wire-grid polarizer reflects the light in the image beam away from the screen. The reflected image beam then encounters a ¼-wavelength achromatic retarder that converts the linear polarization to circular polarization. The image beam next hits a mirror that reflects the light back through the ¼-wavelength achromatic retarder, which converts the circular polarization back to linear polarization, with the polarization director rotated 90 degrees from the original polarization direction. The wire-grid polarizer then allows the light to pass through to the image screen.
摘要:
An optical polarization beam combiner or separator device includes a first optical beam carrier for carrying a first polarized beam and a second optical beam carrier for carrying a second polarized beam whose polarization is orthogonal to the polarization of the first polarized beam. First and second collimating/focusing lenses are positioned between the first and second optical carriers. A third optical beam carrier for carrying a non-polarized beam positioned on the same side of the two collimating/focusing lenses as the first optical beam carrier. An inorganic, dielectric grid polarizer is disposed between the first and second collimating/focusing lenses, and includes a stack of film layers disposed over a substrate. Adjacent film layers have different refractive indices. At least one of the film layers is discontinuous to form a form birefringent layer with an array of parallel ribs with a pitch of less than 400 nm, and greater than 200 nm.
摘要:
A light recycling system includes a light source capable of producing a visible light beam. An inorganic, dielectric grid polarizing beam splitter is disposable in the light beam to separate the light beam into two light beams of orthogonal polarization orientation including a transmitted beam and a reflected beam. The grid polarizer includes a stack of film layers disposed over the substrate. Each film layer is formed of a material that is both inorganic and dielectric. Adjacent film layers have different refractive indices. At least one of the film layers is discontinuous to form a form birefringent layer with an array of parallel ribs with a period less than approximately 260 nm. Light reorientation means is disposable in the transmitted or reflected beam for changing the polarization orientation of the transmitted or reflected beam.
摘要:
A projection display or modulation optical system includes a spatial light modulator and an inorganic, dielectric grid polarizer. The spatial light modulator selectively encodes image information on a polarized incident light beam and the inorganic, dielectric grid polarizing beam splitter separates the image information from the beam and produces a polarized image bearing light beam. The grid polarizer includes a stack of film layers disposed over a substrate; each film layer being formed of a material that is both inorganic and dielectric; adjacent film layers having different refractive indices; and at least one of the film layers being discontinuous to form a form birefringent layer with an array of parallel ribs with a period less than approximately 260 nm.
摘要:
An image projection system includes one or more wire grid polarizing beam splitters and one or more transmissive arrays. A polarized light beams from a light source and pre-polarizer is directed towards the transmissive array which modulates the polarization of the polarized light beam by selectively altering the polarization of the polarized light beam to encode image information thereon and creating a modulated beam. The modulated beam is directed towards the wire grid polarizing beam splitter which acts as an analyzer to separate the modulated beam into reflected and transmitted beams. A screen is disposed in one of the reflected or transmitted beams to display the encoded image information. The polarizing beam splitter is oriented at an angle with respect to the modulated beam such that the reflected beam is directed away from the transmissive array. A plurality of transmissive arrays can be used for different colors. One or more polarizing beam splitters can act as both analyzers and combiners.
摘要:
An inorganic, dielectric grid polarizer device includes a stack of film layers disposed over a substrate. Each film layer is formed of a material that is both inorganic and dielectric. Adjacent film layers each have different refractive indices. At least one of the film layers is discontinuous to form a form birefringent layer with an array of parallel ribs having a period less than 400 nm.