Abstract: An imaging device is formed by a transparent substrate having opposite surfaces on which are formed a plurality of micro aspherical lenses. The axes of the lenses on one surface coincide with the axes of respective lenses on the other surface. A two-dimensional micro lens array constructed by arranging converging lenses having a diameter of approximately several to several hundred micrometers is arranged ahead of a light source, thereby forming a multi-beam spot caused by diffraction in a distant position. A three-dimensional shape can be recognized with high precision by shape recognition means utilizing this multi-beam spot.

Abstract: A projection-type image display device includes a transmissive image display panel having a matrix of pixels arranged at different pitches in different directions perpendicular to each other, and a planar microlens array for converging light emitted by a light source onto the transmissive image display panel. The planar microlens array comprises a substrate and a matrix of microlenses disposed on the substrate for converging the light onto the pixels, respectively, each of the microlenses being of an oblong shape. Each of the microlenses may have a longitudinal axis inclined with respect to an axis of the matrix of pixels to cover the pixel aperture of one of the pixels. The oblong shape of each of the microlenses may be composed of a pair of spaced identical semicircles and a rectangle interconnecting the identical semicircles and having sides of the same length as the diameter of the semicircles.

Abstract: An ophthalmic lens has front and rear optical surfaces, a central optical axis substantially perpendicular to the lens and comprises a plurality of concentric, contiguous circular refractive bands provided on at least one of the front and rear optical surfaces. The bands have a continuous cross-section in the shape of a segment of an ellipse having a given major axis length and eccentricity. The bands are of a given optical power to focus light on the focal plane. The major or the minor axis of each ellipse segment intersects the central optical axis and the focal plane. The bands are continuous at their boundaries between neighboring ones of the bands. The entire optical surface of the lens may be used with minimal distortion caused by the intersections of the continuous bands.

Abstract: In a fly-eye lens device according to the present invention, a fly-eye lens supported by supporting means is formed by two-dimensionally arranging plural types of fly-eye constituent lenses of unequal size. In the arrangement, the plural types of the fly-eye constituent lenses are disposed in order of ascending size from the center of the fly-eye lens toward the periphery thereof. A lighting system according to the present invention is equipped with the fly-eye constituent lenses. In the lighting system, light emanating from a light source passes through first optical means and impinges on the fly-eye constituent lenses. The light, after passing through a stop, is directed through second optical means to an object to be illuminated. The present invention can ensure the predetermined number of fly-eye constituent lenses which contribute to uniformity of illumination, and achieve uniform illumination at low cost.

Abstract: An ophthalmic lens has front and rear optical surfaces, a central optical axis substantially perpendicular to the lens and comprises a plurality of concentric, contiguous circular refractive bands provided on at least one of the front and rear optical surfaces. The bands have a continuous cross-section in the shape of a segment of an ellipse having a given major axis length and eccentricity. The bands are of alternating optical power to focus light on at least two focal planes to provide simultaneous multifocal vision. The major axis of each ellipse segment intersects the central optical axis and a respective one of the at least two focal planes. The bands are continuous at their boundaries between neighboring ones of the bands. The entire optical surface of the lens may be used with minimal distortion caused by the intersections of the continuous bands.