3m Innovative Properties Company

Minnesota Mining and Manufacturing Company

Eyesee360, Inc.

Gamma Scientific Inc.

Stephen K Eckhardt

Charles L Bruzzone

Jiaying Ma

David J W Aastuen

Gary Timothy Boyd

Simon Magarill

John Allen Wheatley

Michael F Weber

David F Slama

David Jon Lundin

David Adams Ender

Barry S Carpenter

Mark E Napierala

Todd S Rutherford

Jennifer J Sahlin

Roger J Strharsky

R Edward English, Jr

E Gregory Fulkerson

Karl A Vick

Michael K Domroese

Tao Liu

James N Dobbs

Glendon D Kappel

Dwight G Baldwin

Linda Mae Rivard

Hamid R Mortazavi

Brian A Kinder

Chun-Yi Ting

Norbert L Johnson

Han-Lin Tung

Michael J Raykowski

Light assembly having reflector, light source, an outer light cover, and a curved transflective surface. Embodiments of light assemblies described herein are useful, for example, as signs, backlights, displays, task lighting, luminaire, and vehicle (e.g., cars, trucks, airplanes, etc.) components. Vehicle comprising light assemblies include those where the light assembly is a vehicle tail light assembly.

Light assembly

Panoramic optical systems are disclosed comprising an ellipsoidal mirror and a lens system that reduces astigmatism. The lens systems are capable of operating at fast speeds. Simple and highly manufacturable lens systems are provided for capturing and/or projecting high quality 360-degree panoramic scenes.

Panoramic optical systems

Light assembly () having reflector (), light source (), an outer light cover (), and a curved transflective surface (). Embodiments of light assemblies described herein are useful, for example, as signs, backlights, displays, task lighting, luminaire, and vehicle (e.g., cars, trucks, airplanes, etc.) components. Vehicle comprising light assemblies include those where the light assembly is a vehicle tail light assembly.

A back reflector for a lightguide in a turning film backlight includes a prism film layer in direct contact with a reflective layer. The lightguide includes a light guiding region having a refractive index that is substantially spatially uniform. The reflective layer may be specular or diffuse and may include a multilayer polymeric film.

Backlight reflectors having a prismatic structure

The present invention comprises various embodiments of a retroreflectometer capable of measuring the retroreflectance of a material. The retroreflectometer comprises an illumination path and a retroreflection path. The illumination path comprises focusing optics, a source aperture, a beamsplitter and a collimating lens. The retroreflection path comprises a focusing lens, a beamsplitter, a receiver aperture and a receiver. The source aperture shapes the transverse profile of the light to make it appropriate to the measurement. Focusing optics, such as a biconvex lens, may be placed between the light source and the source aperture. After the beam is reflected by the object under test, it enters the retroreflection path of the instrument. The focusing lens focuses the light through the beamsplitter and onto the receiver aperture. The receiver aperture may be the input slit for a spectrometer, or there may be optics, such as a lens or an optical fiber, that transfer the light from the aperture to the receiver. A photopically corrected detector, multiple detectors with filters or a spectrometer may be used in various embodiments of the present invention as the receiver.

Apparatus for measuring the retroreflectance of materials

A microreplicated achromatic lens is disclosed. The article includes a web including first and second opposed surfaces. The first surface includes a first microreplicated structure having a plurality of first features. The second surface includes a second microreplicated structure having a plurality of second features. Opposing first and second features are registered to within 10 micrometers. Corresponding opposed first and second features cooperate to form an achromatic microlens element.

Microreplicated achromatic lens

Provided is a Fresnel lens for use with an array of semiconductor pixels that are separated by inactive areas, comprising a faceted surface with a plurality of facets for receiving an imaging beam, the facets being arranged into a plurality of zones separated by zone edges, and wherein the zone edges are generally aligned with the inactive areas throughout the array. Also provided are an optical detector and an imaging system incorporating such a Fresnel lens system.

Fresnel field lens

An optical unit that includes a polarizing beamsplitter (PBS). The PBS includes a reflective polarizer that transmits a portion of a light beam that has a first polarization and reflects a portion of the light beam that has a second polarization. A light absorbing device is operatively disposed relative to the PBS. The light absorbing device receives the light either transmitted or reflected by the PBS. The light absorbing device includes a light capture portion having a structured surface.

Polarizing beamsplitter assembly

A color-splitting optical element is disclosed that includes a first prism having a first transmissive curved outer side, a second transmissive curved outer side and an inner side. The color-splitting optical element also includes a second prism having a first transmissive curved outer side, a second side and an inner side. A dichroic element is disposed between the inner side of the first prism and the inner side of the second prism. The first transmissive curved outer side of the first prism is disposed generally opposite the first transmissive curved outer side of the second prism along a first direction and the second transmissive curved outer side of the first prism is disposed generally opposite the second side of the second prism along a second direction. Also disclosed are optical systems utilizing such color-splitting optical elements.

Color-splitting optical element and an optical system utilizing the color-splitting optical element

Generally, the present invention relates to an apparatus for reducing astigmatism in a projection system that is particularly well suited to reducing astigmatism in LCD projection systems. A projection system includes a light source to generate light, conditioning optics to condition the light from the light source and an imaging core to impose on image on conditioned light from the conditioning optics to form image light. The imaging core includes a polarizing beamsplitter and at least one imager, and at least one element in the imaging core is adapted to reduce astigmatism in the image light. The astigmatism may arise in the polarizing beamsplitter. A projection lens system projects the astigmatism-reduced image light from the imaging core.

Projection system having low astigmatism

A projector illumination system includes a tunnel integrator incorporated with a field lens at its output end. One advantage of using the field lens is to form an image of the entrance end of the tunnel integrator at the secondary stop of the illumination system when combined with other relay and/or imager field lenses in the illumination system. This reduces vignetting, resulting in an increased uniformity of illumination, and increased light throughput.

Projection illumination system with tunnel integrator and field lens

A compound polarization beam splitter () for use with a reflective, polarization-modulating, imaging device (), e.g., a LCoS device, is provided. The compound PBS has: (a) an input prism (); (b) an output prism (), and (c) a polarizer (), which is located between the two prisms () and which may be a wire grid polarizer () or a multi-layer reflective polarizer (). Polarized illumination light () enters the input prism () through a first surface () and undergoes total internal reflection at a second surface () before being reflected from the polarizer () and polarization-modulated at the imaging device (). The polarizer's tilt angle (&#x3b2;) is less than 45&#xb0;, which reduces astigmatism and the required back working distance of the system's projection lens ().

Compound polarization beam splitters

A compound polarization beam splitter ( ) for use with a reflective, polarization-modulating, imaging device ( ), e.g., a LCoS device, is provided. The compound PBS has: (a) an input prism ( ); (b) an output prism ( ), and (c) a polarizer ( ), which is located between the two prisms ( ) and which may be a wire grid polarizer ( ) or a multi-layer reflective polarizer ( ). Polarized illumination light ( ) enters the input prism ( ) through a first surface ( ) and undergoes total internal reflection at a second surface ( ) before being reflected from the polarizer ( ) and polarization-modulated at the imaging device ( ). The polarizer's tilt angle (&bgr;) is less than 45&deg;, which reduces astigmatism and the required back working distance of the system's projection lens ( ).

An optical imaging system including a wide-angle Cartesian polarizing beam splitter, light valve illumination optics having an f/&num;&lE;2.5, and at least one reflective light valve. The Cartesian polarizing beam splitter (PBS) has a structural orientation defining fixed polarization axes. The use of a Cartesian PBS allows the development of systems using curved PBS that provide higher light output and/or replace or augment other optical components. By recognizing and advantageously applying properties of wide-angle Cartesian polarizers, the present invention discloses a high-efficiency optical imaging system capable of functioning at f/&num;'s equal to or below f/2.5 while maintaining a contrast ratio of at least 100 to 1, or, more preferably, 150 to 1 in a projection system configuration.

Growing community of inventors

White Bear Lake, MN, United States of America

Stephen K Eckhardt