Abstract: A collimating image-forming apparatus comprising a first linear polarizer is disclosed. A first quarterwave plate is disposed adjacent the first polarizer and has its fast and slow axes at substantially 45° to the plane of polarization of the first polarizer. The apparatus further comprises a beam-splitting curved mirror having a convex surface adjacent the first polarizer and facing towards the first quarter-wave plate, a second quarter-wave plate adjacent the concave side of the curved mirror, the second quarterwave plate having its having its fast and slow axes oriented with respect to the corresponding axes of the first quarter-wave plate at angles substantially equal to a first integral multiple of 90°, and a reflective-transmissive polarizing member adjacent the second quarter-wave plate.

Abstract: The embodiments herein describe how if a narrow wave length notch of light is used to illuminate or create an image source then the beam-splitter is only required to transmit over the narrow wavelength notch. If the concave mirror only reflects the same wavelength notch then all other wavelengths will pass through the mirror and be reflected by the beam-splitter. Each of the embodiments uses a method of optical design wherein certain portions or elements of the optical system are used for multiple purposes and/or transmit certain paths of light transmission in multiple directions. This use of multiple purposes and multiple paths produces embodiments of the invention that are smaller and more robust.

Abstract: A first embodiment is a lens system having a plurality of refractive and reflective spherical elements that work as a magnifier to produce a distortion free, less than 1%, image with optical correction over a wide field of view. The system has at least one concave reflecting surface, and at least three convex refracting surfaces with the sign of the radius of one of the convex refracting surfaces being opposite of the sign of the radius of remaining two convex refracting surfaces. A second embodiment is a lens having a concave reflecting element which is on a substrate that is a negative lens by transmission with an index of refraction between 1.6<nd >2.0 and a dispersion 49<?d>15. This is used in combination with at least 3 positive refracting surfaces with less dispersive power than the negative element and with the sign of the radius of one of the positive elements being opposite from the sign of the radius of the remaining positive elements.

Abstract: A collimating image-forming apparatus comprising a first linear polarizer is disclosed. A first quarterwave plate (14) is disposed adjacent the first polarizer (12) and has its fast and slow axes at substantially 45° to the plane of polarization of the first polarizer. The apparatus further comprises a beam-splitting curved mirror (16) having a convex surface adjacent the first polarizer and facing towards the first quarter-wave plate, a second quarter-wave plate (22) adjacent the concave side of the curved mirror, the second quarterwave plate having its having its fast and slow axes oriented with respect to the corresponding axes of the first quarter-wave plate at angles substantially equal to a first integral multiple of 90°, and a reflective-transmissive polarizing member (24) adjacent the second quarter-wave plate.

Abstract: A collimating image-forming apparatus comprising a first linear polarizer is disclosed. A first quarterwave plate is disposed adjacent the first polarizer and has its fast and slow axes at substantially 45° to the plane of polarization of the first polarizer. The apparatus further comprises a beam-splitting curved mirror having a convex surface adjacent the first polarizer and facing towards the first quarter-wave plate, a second quarter-wave plate adjacent the concave side of the curved mirror, the second quarterwave plate having its having its fast and slow axes oriented with respect to the corresponding axes of the first quarter-wave plate at angles substantially equal to a first integral multiple of 90°, and a reflective-transmissive polarizing member adjacent the second quarter-wave plate.

Abstract: A first embodiment is a lens system having a plurality of refractive and reflective spherical elements that work as a magnifier to produce a distortion free, less than 1%, image with optical correction over a wide field of view. The system has at least one concave reflecting surface, and at least three convex refracting surfaces with the sign of the radius of one of the convex refracting surfaces being opposite of the sign of the radius of remaining two convex refracting surfaces. A second embodiment is a lens having a concave reflecting element which is on a substrate that is a negative lens by transmission with an index of refraction between 1.6<nd>2.0 and a dispersion 49<?d>15. This is used in combination with at least 3 positive refracting surfaces with less dispersive power than the negative element and with the sign of the radius of one of the positive elements being opposite from the sign of the radius of the remaining positive elements.

Abstract: The invention relates to compact optical arrangement for a helmet mounted display. The arrangement is well suited to use with spatial light modulators which require front illumination such as LCoS modulators but can also be adapted to rear illuminated devices such as LCD's and to self luminous devices such as OLEDs. The device uses polarization and reflection to make dual use of both volumes and lenses.

Abstract: An electronic viewfinder with a reflective microdisplay and associated optical elements in a design that utilizes one or more folded optical paths to achieve a compact size and volume that may have a dimension of less than 10 millimeters per side. Moreover, the optical design may have an effective focal length that is greater than the spacing of the optical elements from the microdisplay. Various embodiments include a pancake window arrangement with reflective surfaces that are spaced apart from each other and cube beamsplitter eyepieces with folded paths.

Abstract: A collimating image-forming apparatus comprising a first linear polarizer is disclosed. A first quarterwave plate (14) is disposed adjacent the first polarizer (12) and has its fast and slow axes at substantially 45° to the plane of polarization of the first polarizer. The apparatus further comprises a beam-splitting curved mirror (16) having a convex surface adjacent the first polarizer and facing towards the first quarter-wave plate, a second quarter-wave plate (22) adjacent the concave side of the curved mirror, the second quarterwave plate having its having its fast and slow axes oriented with respect to the corresponding axes of the first quarter-wave plate at angles substantially equal to a first integral multiple of 90°, and a reflective-transmissive polarizing member (24) adjacent the second quarter-wave plate.

Abstract: An electronic viewfinder with a reflective microdisplay and associated optical elements in a design that utilizes one or more folded optical paths to achieve a compact size and volume that may have a dimension of less than 10 millimeters per side. Moreover, the optical design may have an effective focal length that is greater than the spacing of the optical elements from the microdisplay. Various embodiments include a pancake window arrangement with reflective surfaces that are spaced apart from each other and cube beamsplitter eyepieces with folded paths.

Abstract: A collimating image-forming apparatus comprising a first linear polarizer is disclosed. A first quarter-wave plate is disposed adjacent the first polarizer and has its fast and slow axes at substantially 45° to the plane of polarization of the first polarizer. The apparatus further comprises a beam-splitting curved mirror having a convex surface adjacent the first polarizer and facing towards the first quarter-wave plate, a second quarter-wave plate adjacent the concave side of the curved mirror, the second quarter-wave plate having its having its fast and slow axes oriented with respect to the corresponding axes of the first quarter-wave plate at angles substantially equal to a first integral multiple of 90°, and a reflective-transmissive polarizing member adjacent the second quarter-wave plate.

Abstract: The eyepiece of the helmet mounted display optics is formed by a beam splitter eyepiece cube and a spherical mirror to create a magnified virtual image of a rear projection screen mounted to the eyepiece cube at a relatively large distance from the observer. The rear projection screen receives an image from a spatial light modulator display which is illuminated by a separate light source.

Abstract: An optical image is generated by an image source and is transmitted to an optical assembly by a fiber optic cable or cables. The optical assembly includes a transmission lens or lenses, rear projection screens and an eyepiece. By using a rear projection screen in the optical assembly, a non-pupil forming arrangement is provided.