Abstract: The present application discloses optical elements for use in applications where high contrast is desirable. The optical elements comprise a multilayer optical film having a plurality of reflection bands at design wavelengths of incident light, wherein at least one of the reflection bands is a narrow reflection band, wherein each reflection band has a nominal spectral position at a design angle of incidence and wherein each reflection band shifts to a color-shifted reflection band for light incident at angles other than the design angles. The optical elements also comprise a wavelength selective absorber for absorbing at least one of the color-shifted reflection bands.

Abstract: A multilayer reflector useable to reflect or transmit light over the visible wavelength range includes optically thick constituent layers. The optical thickness of the constituent layers through the thickness of the reflector defines a layer thickness profile. The layers are arranged so that the thickness profile has a tailored non-uniform distribution, such as a graded distribution or a randomized distribution. The layers desirably have an optical thickness in a range from about one to five or one to ten design wavelengths. The reflector can be a polarizer, reflecting only one normally incident polarization state, or a mirror, reflecting two normally incident orthogonal polarization states.

Abstract: An optical film is provided which comprises a disperse phase of polymeric particles disposed within a continuous birefringent matrix. The film is oriented, typically by stretching, in one or more directions. The size and shape of the disperse phase particles, the volume fraction of the disperse phase, the film thickness, and the amount of orientation are chosen to attain a desired degree of diffuse reflection and total transmission of electromagnetic radiation of a desired wavelength in the resulting film.

Abstract: A detector system, filter therefor, and method of making same is disclosed. The filter includes an interference element having a reflection band disposed primarily in the near infrared, and having a high transmission over most of the visible region. The filter also includes an absorptive element that absorbs light non-uniformly over the visible region. The filter when combined with a semiconductor photodiode or other suitable detector yields a detector system whose spectral responsivity closely matches the visual response of the human eye.

Abstract: Multilayer polymeric films and other optical bodies are provided which is useful in making colored mirrors and polarizers. The films are characterized by a change in color as a function of viewing angle.

Abstract: An optical film is provided which comprises a disperse phase of polymeric particles disposed within a continuous birefringent matrix. The film is oriented, typically by stretching, in one or more directions. The size and shape of the disperse phase particles, the volume fraction of the disperse phase, the film thickness, and the amount of orientation are chosen to attain a desired degree of diffuse reflection and total transmission of electromagnetic radiation of a desired wavelength in the resulting film.

Abstract: A visible wavelength detector and method of making the same is disclosed. A visible wavelength detector includes a semiconductor structure that converts electromagnetic energy into an electrical signal and an interference element that includes polymeric material and substantially reflects normally incident light over a band of near-infrared wavelengths and that substantially transmits normally incident light over visible wavelengths, disposed on the semiconductor structure.

Abstract: 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.