3M Innovative Properties Company

Minnesota Mining and Manufacturing Company

Other

3M Intellectual Properties Company

Sanford Cobb, Jr

David L Wortman

Andrew John Ouderkirk

Michael F Weber

Wade D Kretman

Mark E Gardiner

Kenneth A Epstein

Olester Benson, Jr

Carl A Stover

Brian D Cull

James M Jonza

Keith Michael Kotchick

Alan B Campbell

Richard A Miller

John F Dreyer

Timothy L Hoopman

Roger H Appeldorn

Kazuhiko Toyooka

David I Wortman

Marvin J Niezgocki

Timothy J Nevitt

Gary Timothy Boyd

Philip Edwin Watson

Richard C Allen

John C Nelson

Leland Ray Whitney

Todd R Williams

Dennis F Vanderwerf

Mark B O'Neill

Ellen O Aeling

Elisa M Cross

Susan L Kent

Bettie C Fong

Dan L Fanselow

Kenneth A Aho

Ronald J Tabar

David J Lamb

Frank L Deyak

Terrence M Conder

Robert D Lowrey

William A Hibbard

Paul A Jaster

Arthur A Wegwerth

Andrew McKee

Michael J Leite

Harry B Anderson

Donna M Koeck

Ronald E Bergsten

A backlight includes a lightguide, a light source disposed with respect to the lightguide to introduce light into the lightguide and a turning film. Optical structures are formed in one of an output surface and a back surface of the lightguide. The optical structures are arranged to extract light from the lightguide. A back reflector is disposed adjacent the back surface. The optical structures are formed to include a varying pattern arranged to mask non-uniformities in the output of the lightguide.

Backlight with structured surfaces

A display includes a liquid crystal display panel, an optical cavity producing substantially collimated light and a birefringent reflective polarizer.

Display incorporating reflective polarizer

Optical devices according to the present invention include a multilayer optical film in which at least one of the layers comprises an oriented birefringent polymer. The multilayer optical film exhibits low absorptivity and can reflect light approaching at shallow angles as well as normal to the film.

High efficiency optical devices

A multiple layer reflective polarizeris described. This element is placed between and optical cavityand an LCD moduleto form an optical display. The reflective polarizer reflects some light into the optical cavitywhere it is randomized and may ultimately emerge with the correct polarization to be transmitted out of the display.

Display having a reflective polarizer

A thin, flexible film made of a transparent polymeric material including a structured surface and an opposite smooth surface, wherein light striking either surface, within certain angular ranges, is totally internally reflected. The structured surface includes a linear array of miniature substantially right angled isosceles prisms arranged side-by-side to form a plurality of peaks and grooves. In addition, the perpendicular sides of the prims make an angle of approximately 45&#xb0; with the smooth surface, and when the film is curled the smooth surface lies in a smooth continuous arcuate curve without materially affecting the performance of the film. Because of the film's flexibility and its ability to totally internally reflect light, it may be utilized in a variety of ways, for example, as a collector of solar energy or as a light conduit. The performance of the film may be manipulated to permit controlled light leakage.

Totally internally reflecting thin, flexible film

An optical element, such as a lightguide or an optical film, is formed with a predetermined, programmed pattern of optical structures. The optical structures may be arranged to selectively correct for non-uniformities in the output a lightguide, or may be arranged to otherwise enhance the performance of a display.

Optical elements having programmed optical structures

Optical devices such as backlight assemblies, according to the present invention include a multilayer optical film in which at least one of the layers comprises an oriented birefringent polymer. The multilayer optical film exhibits low absorptivity and can reflect light approaching at shallow angles as well as normal to the film.

Blacklight with structured surfaces

Brightness enhancing reflective polarizer

Optical devices using reflective polarizers and, in particular, diffusely reflective polarizers are provided. Many of the optical devices utilize the diffusely reflecting and specularly transmitting properties of diffusely reflecting polarizers to enhance their optical characteristics. The optical devices include a lighting system which uses a reflector formed from a diffusely reflecting polarizer attached to a specular reflector. Another optical device is a display apparatus which uses a diffusely reflecting polarizer layer in combination with a turning lens which folds shallow angle light toward a light modulating layer. Other optical devices exploit the depolarizing characteristics of a diffusely reflecting polarizer when reflecting light. Still other optical devices use diffusely reflecting polarizers to recycle light and improve display illumination.

Optical devices using reflecting polarizing materials

The present invention includes a backlight system incorporating a back reflector and/or a lamp cavity reflector constructed of a multilayer optical film.

Backlight system with multilayer optical film reflector

A transflector is described which increases efficiency and brightness under both ambient and supplemental lighting conditions in visual display applications. In one embodiment, the transflector includes a reflective polarizing element that reflects one polarization of light and transmits the other. In an alternate embodiment, the transflector includes a reflective polarizing element and a diffusing element such that the transflector diffusely reflects light of one polarization and transmits the other. The transflector is useful for both reflective and transflective liquid crystal displays.

Transflective displays with reflective polarizing transflector

Optical element having programmed optical structures

Growing community of inventors

Lakeland, MN, United States of America

Sanford Cobb, Jr