Spatial light modulator

About: Spatial light modulator is a research topic. Over the lifetime, 9043 publications have been published within this topic receiving 130143 citations.

An illumination system for one-dimensional spatial light modulators employing multiple light sources

Abstract: The present invention is directed to illuminating a one-dimensional spatial light modulator (70) using an illumination system employing multiple light sources (10). The illumination system comprises a parallel array of light sources which provides a plurality of light outputs to an optical train (200). The optical train effectively combines the light sources into a single light source. The single light source provides a single light output for uniformly illuminating the spatial light modulator. The optical train includes a first optical train for receiving the light outputs from each light source, magnifying each light output, and overlaying each of the light outputs to form a single real magnified image. A mode conversion lens receives the single real magnified image, converts a mode profile of the single real magnified image into a top hat mode profile, and outputs a diverging light beam with a top hat mode profile. A second optical train shapes the light beam into an appropriate spatial geometry in such a manner that the light beam effectively illuminates the entire spatial light modulator, and directs the light beam onto the spatial modulator.

Illumination system having an intensity calibration system

Abstract: An illumination system (10) having an automated calibration system (62) for adjusting the light intensity of individual elements (14) of an array of light emitting elements (12). An optical sensor (30) can be positioned in several locations (A,B,C) to sense incident light from a spatial light modulator (20) as the modulator is sequentially actuated one zone (50) at a time. The light output from each zone (50) of the spatial light modulator is characterized and compared to a golden standard, and the light emitting elements of the array associated with illuminating the zones that are deficient in light are ascertained. Adjustment circuitry (62) responsively adjusts and increases the drive current to the associated light emitting elements (14) that are deficient in light output. A look-up table is utilized to determine which LEDs (14) need adjustment to their drive currents to insure uniform illumination in the process and cross-process direction at an image plane. The present invention is ideally suitable for xerographic printers.

Far field subwavelength focusing using optical eigenmodes

Abstract: We report the focusing of light to generate a subdiffractive, subwavelength focal spot of full width half maximum 222 nm at an operating wavelength of 633 nm using an optical eigenmode approach. Crucially, the spot is created in the focal plane of a microscope objective thus yielding a practical working distance for applications. The optical eigenmode approach is implemented using an optimal superposition of Bessel beams on a spatial light modulator. The effects of partial coherence are also discussed. This far field method is a key advance toward the generation of subdiffractive optical features for imaging and lithographic purposes.

Illumination optical system, exposure apparatus, and device manufacturing method

Abstract: An illumination optical system for illuminating an irradiated plane M with illumination light provided from a light source includes a spatial light modulator, which is arranged in an optical path of the illumination optical system and forms a desired light intensity distribution at a pupil position of the illumination optical system or a position optically conjugated with the pupil position, and a diffuser, which is arranged at an incidence side of the spatial light modulator through which the illumination light enters.

Spatial light modulator drive system

Abstract: The spatial light modulator drive system of the present invention permits useful light modulation, such as employed in a projection display device, with a minimum of required data input. A plurality of charge storage cells with associated charge dependent light modulator cells are disposed at the intersection of row and column conductors. The drive system alternately refreshes the data stored in a particular row and responds to external commands. The automatic refresh involves selecting a particular row via a dedicated refresh counter, reading the column data in that row, storing this data in a column latch and rewriting this data to the same row. The generation of a new display is achieved in a number of steps. A particular row is selected by externally applied data. The data type, such as number of bits and variations in shade, is also specified. The starting column for application of new display data enables this new data to be entered into the desired portion of the column latch for application to the desired light modulator cells.