A method of using a photogrammetry system to produce a three-dimensional image representation includes placing an object in the photogrammetry system, illuminating only a plurality of polarized lights, capturing a polarized image capture set of the object using a plurality of cameras while only the plurality of polarized lights are illuminated, and sending the polarized image capture set to the at least one computer processor. The method further comprises illuminating only a plurality of non-polarized lights, capturing a non-polarized image capture set of the object from the plurality of cameras while only the non-polarized lights are illuminated, and sending the non-polarized image capture set to the at least one computer processor. The method still further comprises using the at least one computer processor to generate a three-dimensional image representation of the object includes comparing the polarized image capture set and the non-polarized image capture set.

The present disclosure describes optical elements and optical devices that use the optical elements to allow the output of two imagers to be combined onto a single optical axis. Each of the two imagers can be based on alternate polarization directions, and the disclosed embodiments can enable high contrast 3D projectors without requiring either time or polarization sequencing. The present disclosure further describes projection systems that include the optical devices.

The present invention relates to a time-multiplexed stereoscopic 3d projection system wherein the image-beam from a digital cinema projector is separated by a polarization beam-splitting element into one primary image-beam possessing a first state of polarization and at least one secondary image-beam possessing a second state of polarization. Polarization modulators are provided in order to modulate the polarization state for each of said primary and secondary image-beams thereof and arranged so that all left-eye images possess a first modulated state of polarization and all right-eye images possess a second modulated state of polarization. Additionally, there is provided one uniaxial condensing lens and at least one uniaxial expanding lens in order to minimize the optical path-lengths for each of said primary and secondary image-beams thereof, hence enabling said stereoscopic 3d projection system according to the present invention to operate together with projectors having a shorter throw-ratio as compared to other prior-art technologies.

The present invention relates to a time-multiplexed stereoscopic 3d projection system wherein the image-beam from a digital cinema projector is separated by a polarization beam-splitting element into one primary image-beam possessing a first state of polarization and at least one secondary image-beam possessing a second state of polarization. Polarization modulators are provided in order to modulate the polarization state for each of said primary and secondary image-beams thereof and arranged so that all left-eye images possess a first modulated state of polarization and all right-eye images possess a second modulated state of polarization. Additionally, there is provided one uniaxial condensing lens and at least one uniaxial expanding lens in order to minimize the optical path-lengths for each of said primary and secondary image-beams thereof, hence enabling said stereoscopic 3d projection system according to the present invention to operate together with projectors having a shorter throw-ratio as compared to other prior-art technologies.

A stereoscopic display device includes an image display device to display, for each imaging point inside a space region, an image of an object to be projected to the space region at the relevant imaging point in a block corresponding to the relevant imaging point on a display region, a lens to direct light beams given out from the respective blocks to mutually different directions, a light guide plate having first deflectors provided in any of an emission surface and a surface opposed to the emission surface, each of the first deflectors directing the light beams entering the light guide plate to mutually different directions to emit the light beams from the emission surface, and a second deflector configured to direct, for each of the first deflectors, the light beam from each of the blocks emitted from the emission surface through the first deflector to the corresponding imaging point.

A stereoscopic display device includes an image display device to display, for each imaging point inside a space region, an image of an object to be projected to the space region at the relevant imaging point in a block corresponding to the relevant imaging point on a display region, a lens to direct light beams given out from the respective blocks to mutually different directions, a light guide plate having first deflectors provided in any of an emission surface and a surface opposed to the emission surface, each of the first deflectors directing the light beams entering the light guide plate to mutually different directions to emit the light beams from the emission surface, and a second deflector configured to direct, for each of the first deflectors, the light beam from each of the blocks emitted from the emission surface through the first deflector to the corresponding imaging point.

A polarized image acquisition section 20 acquires a plurality of polarized images having different polarization directions. The polarized images show, for example, an input indicator for a user interface as a recognition target object. A normal line calculation section 30 calculates normal lines for individual pixels of the recognition target object in accordance with the polarized images acquired by the polarized image acquisition section 20. The normal lines represent information based on the three-dimensional shape of the recognition target object. A recognition section 40 recognizes the object by using the normal lines calculated by the normal line calculation section 30, determines, for example, the type, position, and posture of the input indicator, and outputs the result of determination as input information on the user interface. The object can be recognized easily and with high accuracy.

A polarized image acquisition section 20 acquires a plurality of polarized images having different polarization directions. The polarized images show, for example, an input indicator for a user interface as a recognition target object. A normal line calculation section 30 calculates normal lines for individual pixels of the recognition target object in accordance with the polarized images acquired by the polarized image acquisition section 20. The normal lines represent information based on the three-dimensional shape of the recognition target object. A recognition section 40 recognizes the object by using the normal lines calculated by the normal line calculation section 30, determines, for example, the type, position, and posture of the input indicator, and outputs the result of determination as input information on the user interface. The object can be recognized easily and with high accuracy.

A projection system is provided, including: a projection unit to output a projection image; a retardation plate arranged obliquely with respect to an optical axis of the projection image, the retardation plate to modulate a polarization state of the projection image incident thereon; a reflective polarizing plate stacked on a side of the retardation plate opposite to that on which the projection image is incident, the reflective polarizing plate to reflect a first polarization component of the projection image transmitted through the retardation plate; and a retro-reflective element provided along a direction in which the projection image is reflected by the reflective polarizing plate, the retro-reflective element to output reflected light against a direction in which the light is incident, wherein the reflective polarizing plate transmits a second polarization component of the projection image reflected by the retro-reflective element and modulated by the retardation plate.

Shaped glasses have curved surface lenses and spectrally complementary filters disposed on the curved surface lenses configured to compensate for wavelength shifts occurring due to viewing angles and other sources. The spectrally complementary filters include guard bands to prevent crosstalk between spectrally complementary portions of a 3D image viewed through the shaped glasses. In one embodiment, the spectrally complementary filters are disposed on the curved lenses with increasing layer thickness towards edges of the lenses. The projected complementary images may also be pre-shifted to compensate for subsequent wavelength shifts occurring while viewing the images.