Abstract: A cell for casting resinous ophthalmic lenses including an annular gasket of resilient material and a pair of meniscus glass mold halves between which a lens may be cast. The mold halves are loaded into one side of the gasket annulus, one fully entered and seated against an inwardly directed locating flange and the other peripherally snapped into an annular receiving groove spaced away from the flange.

Abstract: Ophthalmic lens surfacing with preformed tools (laps) requires the traditional blocking and pressing of a lens against the tool with force applied to the block. Lens blocks being thereby geometrically decentered in many of larger diameter lenses causing force applied to the block to be unevenly distributed over the lens-tool surfacing interface. This being detrimental to final lens surface shape and finish is avoided according to the present invention by the provision of a universally adjustable lens block adaptor designed to receive and distribute the surfacing pressure uniformly over the lens-tool interface.

Abstract: Glass lenses, or lens blanks, containing all the ingredients necessary to produce phototropic, or photochromic, behavior, are treated in a conventional production furnace to produce a locally variable heat treatment, wherein at least one portion thereof is raised to a temperature exceeding the glass strain point but not the softening point, and other portions are heated to variable temperature decreasing from the strain point. The treatment causes development of phototropic, or photochromic, behavior only in those portions of the lenses, or lens blanks, exposed to the temperature above the strain point. The lenses resulting are characterized by trichromatic coefficients, x=0.306 and y=0.307, in the unactivated state and x=0.324 and y=0.321, in an activated state and including a small but effective quantity of cobalt oxide.

Abstract: A chemically durable, biologically inert optical implant lens formed of a low density natural or synthetic crystal, such as Corundum, Sapphrie, Ruby, Sircon, Strontium Titanate, Diamond, Anatase or Ruby.

Abstract: Glass lenses, or lens blanks, containing all the ingredients necessary to produce phototropic, or photochromic behavior, are treated in a conventional production furnace to produce a locally variable heat treatment, wherein at least one portion thereof is raised to a temperature exceeding the glass strain point but not the softening point, and other portions are heated to variable temperatures decreasing from the strain point. The treatment causes development of phototropic, or photochromic, behavior only in those portions of the lenses, or lens blanks, exposed to the temperature above the strain point. The lenses resulting are characterized by trichromatic coefficients, x=0.310 and y=0.321, in the unactivated state and x=0.314 and y=0.319, in an activated state.

Abstract: A conventional pressure cuff is attached to a living test subject. First means are provided for changing pressure in the cuff and thereby applying pressure to the subject. Second means communicating with the cuff are provided for measuring a quantity proportional to a time-dependent fluctuating component representative of pulsatile pressure within a blood vessel of the subject, the second means having a frequency response adequate to accurately follow the subject's blood pressure waveform, for instance at least about five times the subject's pulse rate, whereby the fluctuating quantity is proportional to amplitude of pulsatile pressure. The maximum value of the fluctuating quantity is determined as applied cuff pressure is changed.

Abstract: Optical sections (lenses) of pseudophakoi having tangential holes are produced without drilling operations. A preform of lens material is drawn with embedded acid soluble rods and/or openings corresponding in diametral size and relative juxtaposition to the size, shape and locations of holes needed in a lens, a lens blank is cut from the drawn preform and portions of rods remaining therein are etched away prior to or following final edging and surface finishing of the lens blank.

Abstract: A goggle for protection against dust and impact damage to the eyes including a pliable, contoured facemask having a pair of forwardly extending cage portions each adapted to receive and fixedly support a rigid eyecup. Each eyecup, in turn, supports an impact and shatter-resistant safety lens held in place with a resilient O-ring. Sides of the eyecup are provided with openings covered with dust-filtering and impact-resistant double screening. The eyecups are readily manually insertable into and removable from cage portions of the pliable facemask and each, in turn, is adapted to selectively internally support an adapter for an auxiliary ophthalmic prescription lens.

Abstract: A faceshield constructed and arranged to protect against chemical splash and other ambient foreign matter. A main support pivotally attachable to a safety cap carries a depending transparent facepiece detachably connected to the main support beneath an overhang. The connection is made with buttons suspended from the overhang and the overhang, in turn, shields the facepiece connection from direct exposure to splash. Provision for snap-fitting the main support to the safety cap brim avoids accidental displacement of the shield during use while permitting its release and selective pivoting to an out-of-the-way position.

Abstract: The invention pertains to method and apparatus for specimen preparation, in conjunction with which at least one specimen surface is produced on a test piece embedded, if required, in a casting-resin mounting medium through chip or slice removal of material and wherein the examined specimen surface is milled; especially, a method for the preparation of hard objects, and/or objects exhibiting differential hardness over the specimen surface, for electron scan microscopic and X-Ray studies. The invention further includes apparatus for preparing a specimen for examination which includes a milling head.

Abstract: An optical element is provided having a durable abrasion-resistant, antifog coating applied to at least one surface thereof by coating an optical element comprised of an inorganic or organic transparent base with a transparent abrasion-resistant antifog coating consisting of a lightly cross-linked polyvinyl alcohol, the desired degree of cross-linking being obtained by utilizing a combination of zirconium nitrate and formaldehyde as cross-linking agents.

Abstract: A progressive power ophthalmic lens is described on which one refractive surface is formed to provide zones at the top and bottom of the refractive surface having constant dioptric focal powers. The two zones having constant dioptric focal power are of different radii of curvature such that a near viewing zone is located at the bottom and a distance viewing zone is located at the top of the refractive surface. Between these two constant dioptric focal power zones lies an intermediate zone having progressive dioptric focal power within a range centered between the dioptric focal powers of the upper and lower zones. There is a downwardly positive discontinuity in the dioptric focal power at the boundary between at least one of the constant dioptric focal power zones and the intermediate zone having progressive dioptric focal power. This power discontinuity lowers the rate of addition of dioptric focal power through the progressive power intermediate zone.

Abstract: The invention pertains to method and apparatus for specimen preparation, in conjunction with which at least one specimen surface is produced on a test piece embedded, if required, in a casting-resin mounting medium through chip or slice removal of material and wherein the examined specimen surface is milled; especially, a method for the preparation of hard objects, and/or objects exhibiting differential hardness over the specimen surface, for electron scan microscopic and X-Ray studies. The invention further includes apparatus for preparing a specimen for examination which includes a milling head.

Abstract: Refractive characteristics of the eye or eyes of a microscopist can result in an unfocused image in the film plane of a camera attachment if accommodation occurs in the objective focusing system and an unfocus image can be prevented by providing a separate image for adjustment of the eyepiece or eyepieces to accommodate refractive characteristics of the eye or eyes of the microscopist independent of the object focusing mechanism.

Abstract: A progressive power ophthalmic lens is described on which one refractive surface is formed to provide zones at the top and bottom of the refractive surface having constant dioptric focal power. The two zones having constant dioptric focal power are of different radii of curvature such that a near viewing zone is located at the bottom and a distance viewing zone is located at the top of the refractive surface. Between these two constant dioptric focal power zones lies an intermediate zone having progressive dioptric focal power between the dioptric focal powers of the upper and lower zones. The intermediate zone makes a smooth optical connection to each of the other zones so that the refractive surface is continuous over its entire area.

Abstract: A device for use in the art of fitting lenses to spectacle frames wherewith ophthalmic measurements are applied directly to frames selected by patients. A frame without lenses is adjusted to fit the patient, the measuring device is then applied to the frame and the whole placed upon the face. Horizontal and vertical measurements of distances from lateral and inferior points on the frame rims to a desired location of lens optical center relative to pupil are made for each eye and these measurements are forwarded to the lens finishing shop for edging and fitting of the lenses.

Abstract: A multifocal ophthalmic lens is described on which one refractive surface is formed to provide a plurality of vertically juxtaposed viewing zones each of which has constant dioptric focal power. The constant dioptric focal power in the various zones increases successively from top to bottom of the multifocal ophthalmic lens. The refractive surface in the zones other than the viewing zone having the lowest focal power at the top of the lens is divided into a plurality of laterally disposed areas. In those areas near the periphery of the lens, the lens is provided with an aspheric surface formed from sections of a figure of revolution such that the principal axes of astigmatism lie in vertical and horizontal planes so that a wearer of the multifocal ophthalmic lens continues to perceive horizontal lines as being horizontal and vertical lines as being vertical and unbroken.

Abstract: There is disclosed a process for improving the adhesion of an evaporable glass coating on a synthetic polymer sheet material by the application of a base vitreous coating of a mixture of silicon dioxide and silicon monoxide by evaporating silicon monoxide under vacuum in an oxygen atmosphere so that in addition to silicon monoxide, a silicon dioxide condensate is condensed on the outer surface of the sheet. An outer vitreous coating is subsequently applied over said base coating. The evaporative glass outer coating can be formed essentially from boron oxide and silicon dioxide containing less than 5% by weight of sodium oxide. The evaporative glass coating can also be of fused silica, or a boro-silicate glass sold under the trademark "Pyrex".

Abstract: Ultramicrotomes conventionally use a glass fragment, or fragment of similar material, as a knife. Such knives have the disadvantage of an uneven back surface inherent in the production of such a knife by fragmentation. Using the complementary fragment and mounting the same slightly spaced from the knife back, provides an anti-curl device. A knife holder, having a groove in which the knife fragment is mounted and a pivoted member with a matching slot to hold the anti-curl device, provides positioning of the anti-curl device and provides access to the specimen when the anti-curl device is pivoted out of proximity of the cutting edge.

Abstract: A lens suitable for implantation in the eye is provided with iris clips of wire each having at least one end locked to the lens by an interference fit in an opening in the lens body. A leader of a cross-sectional size freely insertable through the opening is formed upon the wire, inserted through the opening and used to forcefully draw the adjacent full diameter portion of the wire into the lens to produce the interference fit. The leader is cut away and partial retraction of the thus fitted wire can be effected to recess its terminus.