Prior to the production of microlenses (29) by the reactive ion etch technique, a pattern of notches (25) is formed in a second surface of a substrate (11) opposite a first surface on which the microlenses (29) are to be formed. Reactive ion etching of the first surface to produce the microlenses is sufficiently deep to reach the pattern of notches, thereby to separate the substrate. The array of notches may define, for example, an array of first areas (26) on the second surface, each area being surrounded by a notch. Photoresist elements (28) are then each located on an area of the first surface corresponding to a first area of the second surface, so that the separation separates the substrate into a plurality of segments (26) each containing only one of the microlenses (29). The notches can be made such that each of the segments (26) is cylindrical so that each of the microlenses formed from the substrate has a circular outer periphery.
A resist having a three-dimensional shape of a microlens array and a material layer of the microlens array are simultaneously etched under a condition by which planar patterns transferred from the resist to the material layer are larger than planar patterns of the resist. The spacing between microlenses can be made narrower than the spacing between the planar patterns of the resist. Even when the planar shape of the microlens is an ellipse, the curvatures can be optimized in both the row and column directions by making the heights in these directions different from each other. It is possible to provide a microlens array having a small non-focusing region and a solid-state image pickup device having a high sensitivity and little smear.
A resist having a three-dimensional shape of a microlens array and a material layer of the microlens array are simultaneously etched under a condition by which planar patterns transferred from the resist to the material layer are larger than planar patterns of the resist. The spacing between microlenses can be made narrower than the spacing between the planar patterns of the resist. Even when the planar shape of the microlens is an ellipse, the curvatures can be optimized in both the row and column directions by making the heights in these directions different from each other. It is possible to provide a microlens array having a small non-focusing region and a solid-state image pickup device having a high sensitivity and little smear.
To provide a glass sheet incorporating a plurality of optical elements, which incorporates a plurality of glass optical elements and realizes higher productivity and uniform quality of glass optical elements. The glass sheet incorporating a plurality of optical elements includes a plurality of lens parts formed by molding a glass material, reference surface areas each of which is formed around an outer periphery of each lens part and is horizontal to the lens part, and connection parts each of which extends from one reference surface area and connects one lens part to another lens part, in which the connection part has a margin for facilitating separation of the glass sheet into a plurality of pieces.
A photonic crystal device including a method of forming the photonic crystal device is provided wherein the photonic crystal device comprises a first medium having a thickness and periodically defining a plurality of periodically spaced concave portions. The concave portions having a depth less than the thickness of the first medium. A second medium fills the concave portions. One layer of the device, including both the first and second medium, acts as an optical waveguide layer, or photonic crystal. Another layer is at least partially formed from the first medium, such that the first and second layers share a common medium. A method of forming the photonic crystal device including the steps of applying a resist layer to a first medium, removing portions of the resist layer and corresponding portions of the first medium to form vacancies, and filling the vacancies with a second medium.
A method for forming many microlenses comparatively easily and effectively is provided. On one end of an optical substrate is formed a plurality of lens planes at regular intervals. Lens areas containing the lens planes are partially covered by an etching mask and etching processing is performed on areas being exposed outside the etching mask to remove the areas to a specified depth. While the lens planes formed on one surface of the optical substrate are being held by a support substrate, polishing processing is performed on another end face of the optical substrate and each microlens formed in the lens areas is separated from the support substrate.
