Eastman-kodak Company

Other

David A Richards

Michael K Budinski

Paul O McLaughlin

John C Pulver

Jayson J Nelson

Phillip D Bourdage

Joseph R Bietry

Paul David Ludington

Eugene G Hill

Henry A McKenna

A cover apparatus for directing a water current to rotate a waterwheel includes a shield comprising a first side panel, a second side panel, and a perimeter panel which define a cavity to receive the waterwheel. The cover apparatus is rotatably mountable to a shaft so that the cover apparatus rotates freely around the shaft to cover selected portions of the waterwheel. Typically, the shield covers one half of the waterwheel so that the water current only flows passed an uncovered half of the waterwheel to rotate the waterwheel. Fins are mounted to the perimeter panel to facilitate rotation of the shield around the waterwheel by the water current. An electricity generation system is described and claimed which uses the waterwheel and the cover apparatus.

Cover apparatus for directing water flow around a waterwheel

An optical component including: a substrate made from heat absorptive glass having a front surface and a rear surface, at least one of said surfaces being a crenulate surface having optical power.

Combined heat filter and condenser lens, a projection type apparatus using such, and a method for fabricating it

A method for making working mold tools for use in a compression molding process for molding optical glass elements from high temperature glasses having T 's in the range of from about 400&deg; C. to about 850&deg; C. An yttria aluminosilicate glass is fabricated by traditional melting and casting processes to thereby make an amorphous base material having a minimum apparent viscosity of 10 poise at the temperature at which the optical glass elements are to be molded. A mold preform is made from the base material. A first surface figure for the optical element to be molded with the working mold tool is defined. A second surface figure for a master mold tool and a third surface figure for the working mold tool are computed based upon the first surface figure and the coefficients of thermal expansion of the optical element, the master mold tool, and the working mold tool, the temperature at which the working mold tool is molded, and the temperature at which the optical element is to be molded. A master mold tool is then ground and polished to achieve the second surface figure. The working mold tool is then molded from the mold preform using the master mold tool.

Glass mold material for precision glass molding

A method and apparatus is disclosed for compression molding arrays optical elements which may be later singulated. The apparatus includes first and second mold halves with the second mold half having a central nest and a plurality of predetermined negative optical surface features therein. A glass preform is placed in the central nest and the first and second mold halves and the glass preform are heated to at least the glass transition temperature of the glass preform. The glass preform is then pressed between the first and second mold halves to thereby form an integral array of optical elements with each of the optical elements being a positive of the predetermined negative optical surface features. The integrally formed array of optical elements is then cooled to below the glass transition temperature and removed from the first and second mold halves.

Mold and compression molding method for microlens arrays

A method for making preforms for use in a glass lens molding process and molding lenses is disclosed. A glass rod is formed preferably by dipping a bob into a homogeneous melt of a predetermined optical glass, maintaining the temperature of the homogeneous melt at least the melt temperature and producing a rod of glass from the homogeneous melt, allowing the rod of glass to cool and solidify, and then cutting the rod of glass into predetermined lengths. By withdrawing the bob at a predetermined pull rate the rod of glass can be produced with a predetermined diameter. Using a constant pull rate, the rod of glass will be cylindrical in shape and can be cut into a series of individual cylindrical preforms. The preforms can be inserted into a compression molding apparatus for the forming of a glass optical element therewith. The orientation of the preform is such that the cut planar surfaces of the preform are parallel to the direction of compression of the molding process. The preforms formed by the process exhibit both good surface quality and good internal quality. Orientation of the preform with the cut surfaces parallel to the direction of compression in the final compression molding operation ensures that the optical quality surface of the preform formed by surface tension will be the optical surface of the lens formed therewith and the cut or sawed surfaces of the preform will make up the periphery of the final lens.

Method for fabricating glass preforms for molding optical surfaces in glass elements

A high numerical aperture objective lens for focusing a laser beam consists of a first lens element of positive optical power intercepting the laser beam and a second lens element of positive optical power located adjacent to the first lens element. The first lens element and the second lens element have identical surface profiles.

High numerical aperture objective lens

A method for precision polishing non-planar, aspherical surfaces in substrates having variations in figure which are within an order of about ten wavelengths (10 .lambda.) is performed by coating the non-planar, aspherical surface with a thin, uniform layer of material, single-point-diamond turning the layer to achieve a layer surface with an excellent surface figure, and etching the layer surface down into the substrate to completely remove the layer thereby transferring the excellent surface figure to the substrate.

Process for generating precision polished non-plannar aspherical surfaces

A method for producing diffractive optic molding tools with improved durability is accomplished by depositing a layer of chromium carbide on a substrate material. This layer of chromium carbide becomes the receptor for a final machinable coating such as electroless nickel. The pattern for the desired diffractive surface is predetermined and a single-point-diamond turning machine is used to cut the negative of this predetermined pattern into the machinable layer to produce the pattern of concentric zones to the required depths. The pattern is then uniformly etched in the machinable layer down into the intermediate layer of chromium carbide resulting in the complete removal of all of the electroless nickel. In that the etching rates of electroless nickel and chromium carbide differ from one another, it is necessary to dimensionally adjust the negative pattern turned into the electroless nickel surface to allow for the different etch rates. In such manner, an extremely durable molding surface of chromium carbide is achieved.

Method for fabricating tools for molding diffractive surfaces on optical

A method for precison polishing non-planar, aspherical surfaces in substrates, particularly surfaces of molding tool substrates for molding optical surfaces therewith, which is accomplished by coating the non-planar, aspherical surface with a layer of material having a melt temperature which is less than a temperature at which the substrate will distort, heating the layer of material coated on the non-planar, aspherical surface to at least the melt temperature thereby flowing the layer of material to yield a surface tension smooth surface superimposed over the non-planar, aspherical surface, and etching the surface tension smooth surface down into the substrate to completely remove the layer.

Method for precision polishing non-planar, aspherical surfaces

A glass preform, including a core glass adversely affected by interaction with a molding tool, is provided with a thin surface layer of glass components that are inert to the tool and have an index of refraction that matches the core glass. More specifically, the thin layer comprises glass components having respective indexes of refraction above and below the core index of refraction, in an amorphous mixture that matches the core index. According to certain features, the core glass is flint glass including greater than five percent by weight of titania, and the glass components include mixtures of silica or indium and tin oxide applied in a layer having a thickness between one hundred and one thousand angstroms. Other features of the invention provide a method for making the glass preform and a method for molding a precision optical element using the preform.

Product and process for molding glass lenses

An improved tool is provided for pressing glass into a precision optical element having a strong concave surface. The tool is selected from ceramic and metal materials having coefficients of thermal expansion greater than the coefficient of the pressed glass. Preferred tools include a base material selected from Invar, steel and alumina with a surface layer selected from alumina, zirconia, chromium oxide and chromium carbide, having a finished thickness in the range between ten to two thousand angstroms.

Product for molding glass lenses having difficult shapes

An optical element for collimating and rectifying divergent incident radiation comprises a first optical surface and a second optical surface titled with respect to the first optical surface. The first optical surface has sufficient power to collimate incident radiation, while the second optical surface is tilted sufficiently to provide rectification.

Combination collimating lens and correcting prism

A single hybrid optical element combines reflective and refractive imaging. The optical unit utilizes a dual-reflector outer annulus zone and a refractive inner zone to achieve a high numerical aperture. This system is particularly suitable for, but not limited to, microscope objectives or for digital data storage applications.

Parallel catadioptric optical element

Multiple leg rope assemblies formed from a single rope. In one embodiment, the single rope is doubled into equal length legs lashed side-by-side forming a looped eye at one end of the assembly, the ends of the rope at the other end of the assembly being formed into a pair of adjacent eyes which together create a clevis for connecting the rope assembly to other rope assemblies or fixtures. In another embodiment, a single rope, the ends of which are spliced together end-for-end to form a continuous loop, is doubled into four equal length legs lashed side-by-side to provide, at each end of the assembly, a pair of adjacent looped eyes which together create a clevis for connecting the rope assembly to other rope assemblies or fixtures. Several rope fittings or fixtures for use with the rope assemblies are disclosed.

Growing community of inventors

Rochester, NY, United States of America

David A Richards