Abstract: A process for forming a channel waveguide in which the channel geometry and the channel index of refraction vary oppositely along the channel length to keep the modal characteristic of the channel uniform uses non-uniform heating of a channel waveguide to cause non-uniform diffusion of the channel dopant. In one embodiment, the channel is passed under a laser at a non-uniform rate to expose the channel to different numbers of laser pulses.

Abstract: Heretofore, two approaches have been utilized to improve storage stability, particularly a reduction in the tendency for caking during storage, of freshly prepared urea particles: (1) treat the surface of freshly prepared urea particles with conditioning agents, or (2) incorporate, within the urea particles, by means of addition to the urea melt, certain chemicals which act as hardening agents. This invention is directed to approach (2) supra, and by way of coincidence, to a third approach, to wit, utilizing a gelling clay as said additive to also act as an in situ suspending agent in instances wherein said treated urea is utilized in the subsequent production of suspension type fertilizers.

Abstract: In this method of manufacturing a flexible contact lens from a protein biological material, such as a protein polymer of the gelatine type or a type IV enriched human collagen, a hydrogel is first made by hydrating the protein biological material, in water or a physiological serum. A lens preform is then made from the hydrogel at a temperature between ambient temperature and the temperature at which the material liquefies, at which temperature the hydrogel has a paste-like consistency. This preform, which reproduces the shape of the finished lens with a greater or lesser degree of accuracy, but always with excess material, is then placed in a mold made from a low-loss dielectric material. The mold is in at least two parts which, when locked together, define a three-dimensional shape and a finished lens surface state. The hydrogel is then liquefied by irradiating the mold with an electromagnetic field at a frequency between 10.sup.8 and 10.sup.10 Hz.

Abstract: A process for preparing aromatic polyamide fibers wherein an aromatic diamine and an aromatic diacidchloride are dissolved in an amide polymerization solvent containing an inorganic salt, a partial polymerization is effected at a low temperature to form an optically anisotropic liquid crystalline prepolymer dope, and the liquid crystalline prepolymer dope is subjected to a molecular orientating polymerization in a polymerization accelerating-precipitation solvent to provide aromatic polyamide fibers free of a crystal defect layer perpendicular to the fiber axis and having high strength and high degree of molecular orientation.

Abstract: A soft contact lens of PVA having a tensile strength of not less than 10 kg/cm.sup.2, a water content ranging from 40 to 95% by weight, a visible light transparency of not less than 90%, and an oxygen permeability of not less than 30.times.10.sup.-11 cm.sup.3.(STP).cm/cm.sup.2.sec.mmHg. This soft contact lens can be prepared by forming a solution of PVA in a mixed solvent of water and an organic solvent, pouring the PVA solution in a mold having a shape of contact lens, and crystallizing at a temperature of not more than ordinary temperature. The soft contact lens has a high mechanical strength, high water content, high transparency and high oxygen permeability.

Abstract: Apparatus for producing relatively large and dense, relatively dry sulfur particles from molten sulfur comprises a manifold having a number of small, spaced apart, molten sulfur discharge apertures which are sized, according to the rate and pressure head at which the molten sulfur is received, for enabling the sulfur flow from each aperture to be laminar. Included is a vessel for holding a quenching liquid, preferably water. The manifold is mounted above the vessel with the discharge apertures preferably about one quarter inch to about two inches above the quenching liquid surface. Means are included for continuously moving the manifold in a circular path while the moltlen sulfur is discharged from the manifold apertures so that the discharged streams continually contact different regions of the quenching liquid. A conveyor is connected to the vessel for removing particulate sulfur therefrom.

Abstract: Pultrusion with cure by ultraviolet (UV) radiation, for manufacturing FRP wherein a continuous reinforcing material, most commonly, glass roving is first impregnated with a curable liquid resin and pulled through a UV transmittent die having a desired cross section and a sufficient length to effect the cure and, during passage through such a die, the continuous resinous material or FRP material is subjected to exposure to UV radiation to complete the pultrusion. The invention lies in prevention of sticking trend of the uncured resinous material onto the internal wall of the die. The present invention eliminates the sticking trend by a coating on the internal wall of the glass die. Another embodiment of the pultrusion uses a pipe die having a short length which is insufficient to allow completion of the cure reactions, and then, after passing through such a die, the FRP material to be cured is introduced into a medium liquid of UV transmittent type pressure and therein the material is exposed to UV radiation.

Abstract: An improved method of manufacturing a light waveguide cable having a light waveguide bundle of at least one lead with the filling material received in an outer sheath characterized by the method including applying an outer sheath on the bundle with the filling material, said sheath being of a material at least partially light permeable and cross-linking the filling material by irradiating the sheath with light radiation, such as ultraviolet light, which will pass through the sheath to cross-link the filling material.

Abstract: A focal plate for use in camera and a method of manufacturing the same are disclosed. The focal plate comprises an optical plate, a plurality of lens-like uneven portions regularly formed on the surface of the optical material, and a plurality of fine rugged portions formed on each uneven portion, and is manufactured by forming a pyramid or prism relief on a metal plate through mechanical working, subjecting it to an electro-plating to form a honeycomb pattern composed of hexagonal lens faces containing fine rugged portions therein, and then transferring the honeycomb pattern onto a surface of an optical material.

Abstract: The invention is both a method and apparatus for cutting thermoplastic materials in an aesthetically pleasing fashion. A laser is used to cut a preselected pattern in a thermoplastic material, resulting in a removable cutting being created, which is extracted from the material. Using a contrasting color of thermoplastic material, an identical laser cutting is made. The cutting from the first laser cutting operation is mated to the cavity created by the second laser cutting operation, resulting in a mosaic-type thermoplastic material which is pleasing to the eye. To ensure that the by-products of combustion from the laser cutting do not contaminate the heat-sensitive surfaces of the thermoplastic material, a directed source of vacuum is applied to the cutting table to ensure by-products of combustion are directed away from the cutting field.

Abstract: A radiation-sensitive carrier body directly utilized as a stamper has a glass substrate, a first highly adhesive layer securely adhered to the substrate, a radiation-sensitive layer which discharges a gas component upon being irradiated with a laser beam and which locally forms a protuberance due to the absorbed energy, a second highly adhesive layer securely adhered to the specific material of the radiation-sensitive layer and which deforms in accordance with deformation of the layer, and a metal layer which has a high releasability to allow easy separation from a optical disk substrate material such as an acrylic material when the carrier body is used as a stamper substrate for manufacturing optical disks. A protuberance formed on the carrier body such as a continuous spiral protuberance allows formation of a corresponding spiral groove in the acrylic material, serving as a pre-track into which desired information will be digitally written by a user.

Abstract: A fiber optic chemical sensor and the method of making it are provided, such being useful in medical, biological and industrial applications. The sensor includes an optical fiber waveguide having a photocrosslinked polymeric gel at a portion thereof, which gel is crosslinked in place and undergoes substantial volume expansion. A dye is absorbed into the gel, the dye being responsive to different degrees depending on the presence and concentration of any one of particular parameters of a fluid being monitored, such parameters being pH, oxygen concentration, carbon dioxide concentration and the like.

Abstract: Complex small objects such as ophthalmic lenses are quickly and accurately fabricated from plastic or glass blanks of ablatable material such as plastic or glass by cutting, shaping, and radiusing the blank entirely by laser light, using appropriate masks and focusing optics.

Abstract: A mixture of a specified siloxanylalkyl ester monomer and a specified vinyl monomer is polymerized by exposure to an ionizing radiation at low temperatures and the resulting polymer is worked with a lathe cut to form a contact lens. The contact lens obtained is free from any optical distortion, has good dimensional stability and exhibits high oxygen permeability. In a preferred embodiment, a monomer mixture comprising a siloxanylalkyl ester, a methacrylate or acrylate, N-vinylpyrrolidone, and a small amount of a dimethacrylate or diacrylate is exposed to a total dose of 1.times.10.sup.5 -5.times.10.sup.6 roentgens at a low temperature (-80.degree. C. to -20.degree. C. and at a dose rate of 8.times.10.sup.4 -2.times.10.sup.6 roentgens per hour, and the resulting polymer is worked into a contact lens by a suitable forming process involving cutting, grinding and polishing operations.

Abstract: Compact discs are continuously mass produced by continuously rotating a master roller about whose periphery a plurality of optical disc patterns are sequentially arranged in order to form inverse patterns on an elongated film fed to the roller at successive contact locations spaced apart of one another lengthwise of the film during each rotation. Each optical disc has a metallized layer which is protected from damage by the provision of sheets of non-negligible thickness.

Abstract: An improved method and assembly for attaching haptics to intraocular lenses. Method and assembly rely on shaping the attachment ends of plastic or metal haptics so that when inserted into openings in the lens, the haptics are firmly secured to the lens by constraining mechanical forces which arise from an added element, by molding or forming the constraint in situ using an external energy source to melt material of the haptic, or by bending a metal haptic to a holding shape. Melting of lens material is not required for this fastening method or assembly nor is wetting of haptic surfaces by material of the lens necessary.

Abstract: Improved contact lens materials are obtained from copolymers containing a siloxanyl alkyl ester vinyl monomer by exposing the materials to high energy radiation thereby reducing the amount of unreacted monomer and residual contaminants.

Abstract: A method and apparatus for producing fine metal powder. The method includes the steps of forming a centrifugally maintained annulus of a liquified gas quench medium, forming molten metal drops within the eye of the annulus, urging the drops into the quench medium to solidify the drops, and boiling away the quench medium to leave behind clean, unentrained metal powder. The apparatus includes a drum for containing a liquified gas quench medium, means for adding liquified gas to the inside of the drum, and means for rotating the drum to form an annulus of quench medium. The apparatus further includes means for forming molten metal to be made into powder, and means disposed along the longitudinal axis of the drum and within the eye of the annulus for creating molten metal drops. The molten metal drops are then urged into the quench medium to solidify them into a powder, and the quench medium is boiled away to leave behind clean, unentrained metal powder.

Abstract: Spherical gel particles with elastomeric surfaces are made by dripping a liquid silicone gel composition containing alkenyl-containing organopolysiloxane, organohydrogenpolysiloxane, and a platinum catalyst into water or surfactant-containing water, curing and then contacting the surface of the silicone gel particles to organohydrogenpolysiloxane and curing to provide the elastomeric surface. The liquid silicone gel composition can also be extruded in fiber form into the water or surfactant-containing water with stirring to form the spherical particles which are cured and then the surface is contacted with organohydrogenpolysiloxane forming the silicone gel particles with elastomer surface. Alternatively, the liuqid silicone gel composition can be dripped or extruded in fiber form into a liquid having organohydrogenpolysiloxane to form the silicone gel particles with elastomer surface when the particles are cured.

Abstract: A method using one or several successive coatings of an active device (63), (64) by means of a synthetic resin (72);the resin used is on the basis of a product of the family of ethoxy bisphenol A dimethacrylates, to which is added a photo-initiator compound producing radicals by photo-scission or by intermolecular abstraction of hydrogen at a concentration lying between 0.2 and 3% and preferably near 1%, which is then irradiated by ultra-violet radiation (76), as the case may be through a transparent mould (70);Application: coating of semiconductor devices and more particularly optoelectronic devices.

Abstract: The invention discloses an optical disc base plate obtained by curing with irradiation of light a light- or radiation-curable resin composition in which a photopolymerization initiator is contained in an amount of 0.5 to 5 parts by weight per 100 parts by weight of a resin composition comprising the compounds (1), (2) and (3) mixed in amounts falling in the area defined by lines A-B-C-D-E-A in the triangular diagram of FIG.

Abstract: A process for producing a highly uniaxially oriented film is disclosed, comprising supporting a composition comprising two or more liquid crystal monomers displaying a nematic or smectic state and having a polymerizable functional group in the molecule thereof and a photopolymerization initiator on or between a support or supports having been subjected to orientation, and irradiating said composition with radiation while maintaining said composition in a liquid crystal state to cause polymerization of said composition. The resulting film is free from pinholes, strain or unevenness and is excellent in optical transparency.

Abstract: A method of making a substrate for a magnetic recording medium comprises the steps of applying a radiation-polymerizable compound at least to one surface of a base sheet, closely contacting a surface of a transfer member with a surface of a coating layer thus formed of the radiation-polymerizable compound, exposing the coating layer to a radiation from the side of the base sheet or the transfer member, whichever is permeable to the radiation, and separating the transfer member form the surface of the coating layer. The surface of the transfer member is adjusted so that the arithmetical mean deviation at a cut-off value of 0.25 mm and at a measuring length of 80 mm is within the range of 0.001 .mu.m to 0.050 .mu.m, and the ratio of the maximum height at a cut-off value of 0.25 mm and at a measuring length of 20 mm to the arithmetical mean deviation is within the range of 5:1 to 20:1.

Abstract: A system is provided for positioning a pair of electrodes on either side of the end portion of an optical fiber extending through a contact, to establish an arc through a cross-aperture in the contact and across the fiber to melt the fiber into a lens, which assures close control of the arc and which prolongs the life of the electrodes. The tips of the electrodes are positioned to lie slightly within opposite ends of the cross-aperture, to avoid establishing an arc between the electrodes which passes around the contact instead of through the cross-aperture. The electrodes are spaced apart by at least about eight times the diameter of the optic fiber, to avoid deposition of vapors from the heated optic fiber onto the electrodes. The cross-aperture extends to the tip of the contact, so the contact can be moved along its axis to a position where the electrodes lie on opposite sides of the fiber end portion.

Abstract: A pavement marker for roadway surface including a housing 12 having a lower base portion 14 and at least one wall 18 extending substantially upwardly from the base portion 14. A retroreflective lens 20 is mounted on the wall 18 and has a front surface 22 facing away from the wall 18. A photopolymerizable clear acrylic protective hard coat is deposited over the front face of the lens for resisting abrasion of the lens and reducing the loss of optical efficiency resulting from such abrasion.A method of making the pavement marker includes the steps of forming the lens 20 having the front face 22, coating the front face 22 of the lens 20 with a photopolymerizable acrylic composition, irradiating the coating with ultraviolet or electron beam irradiation to cure the acrylic composition to an abrasion resistant coating 24, and mounting the lens 20 in the housing 12 to dispose the coated front face 22 away from the housing 12.

Abstract: A prilling apparatus and process for producing seed material for size enlargement processes such as a granulation process for bisphenol. The apparatus includes a fluidized bed system with a spray header therein for producing spray droplets of material in a gaseous stream such as nitrogen to form prills of less than about 1 mm diameter.

Abstract: A process for the preparation of a substrate for an optical disk having spiral or concentric guide grooves formed on the surface thereof, which comprises the steps of casting a radiation- and heat-curable liquid resin mixture between a duplicating mold and a transport substrate, curing the liquid resin mixture by irradiating it with radiation from the side of the transparent substrate, peeling the molded body from the duplicating mold and heat-polymerizing the obtained molded body by heating, wherein a mixture comprising a liquid resin having a terminal acrylic group and/or a terminal methacrylic group and an organic peroxide is used as the radiation- and heat-curable liquid resin mixture.

Abstract: An apparatus and method is described which is useful in manufacturing molded optical devices. The apparatus and method provide automatic alignment of the mold elements so that cylinder and prism free lenses are provided.

Abstract: A method of attaching a fixation member to an optic comprising providing the optic with a cavity opening adjacent the peripheral edge of the optic with a shoulder in the cavity, inserting an inner end portion of the fixation member into the cavity, transmitting laser energy through the optic to the inner end portion of the fixation member to cause the inner end portion to become flowable, and allowing the flowable portion of the fixation member to harden and interlock with the shoulder to resist withdrawal of the fixation member from the cavity.

Abstract: A method of making optrodes is provided by which a pressure-sensitive volume is incorporated in the optrode by bubble transfer and/or gas entrapment in the manufacturing step sequence.

Abstract: A method and apparatus for producing spherical objects is disclosed, the apparatus having a reservoir filled with a relatively dense molten material, the reservoir being heated and hydraulically pressurized to maintain the molten state of the dense material. A second molten liquid, of lesser density and higher melting point is injected into the reservoir, the pressure and surface tension acting to force the injected material into a spherical form and the melting point difference acting to solidify the injected material.

Abstract: An abrasion-resistant coated plastic lens element and a method for coating the element with an abrasion-resistant coating includes forming a coating on a face of a mold that is substantially cured and adherable to lens-forming material. The coating composition consists of reactants, approximately 70% to 95% of which have at least triacrylate functionality and approximately 5% to 30% of which have diacrylate functionality, a photoinitiator, a polymerization inhibitor reactive with oxygen, and a silane adhesion promoter and an acid to activate the silane adhesion promoter. The coating is applied to the face of the mold to form a substantially uniform coating and is then subjected to ultraviolet light in an ambient oxygen-containing environment such that a hard abrasion-resistant coating is formed on the mold. The mold is then filled with a lens-forming composition which is reactive with acrylate groups of the coating at a coating/lens interface.

Abstract: A method for producing an optical fiber which comprises steps of:spinning an optical fiber from a molten preform for an optical fiber,applying a UV-curable resin to the surface of the spun optical fiber, andirradiating UV light through a layer of a material for absorbing UV light and a layer of a gas for preventing uncuring of the UV-curable resin to cure the UV-curable resin, by which the UV curable resin is homogeneously cured along its length.

Abstract: Low viscosity ethylene acrylic copolymers and blends thereof with other fiber-forming polymers for spunbond and melt blown nonwoven applications. Ethylene/alkyl (meth) acrylate, especially ethylene/methyl acrylate copolymers are found to be suitable for fiber-forming operations, especially melt blowing when the melt index is at least about 10. Blends of the copolymer with other fiber-forming polymers are especially suitable for fiber-forming operations. The nonwoven products of the copolymers and blends of the invention show a good degree of elongation making them especially suitable for certain fabric applications and new uses. The nonwoven fabrics are comprised of fibers of the copolymers and blends, having a diameter of about 1-40 microns. Larger fibers may also be formed by various techniques.

Abstract: A method and apparatus for embossing a pattern having a microscopic relief structure, such as, for example, an optical diffraction grating, onto a layer of thermoplastic material is disclosed. A small circular region of a flexible embossing die is pressed against the thermoplastic layer by means of a punch. A fraction of the corresponding small circular region of the thermoplastic layer is then heated from the rear by a beam of radiant energy. The process may be repeated at all points on the thermoplastic layer where the pattern is desired.

Abstract: A contact lens comprising a lens substrate in shape of a lens which comprises a triorganovinylsilane based polymer, said lens substrate having a hydrophilic polymeric chain grafted onto the surface thereof. This contact lens is not only excellent in oxygen permeability, mechanical strength, dimensional stability, vision correcting ability, staining resistance and handleability, but also good in affinity with eyes due to good hydrophilic property possessed by the surface, which can be worn continuously for a long time.

Abstract: A system is described for forming a lens at the end of an optical fiber which extends through a hole in a contact, so the tip of the lens lies at a desired lens position located a predetermined distance rearward of the tip of the contact. The fiber is fixed to the contact at a position wherein the tip of the fiber lies forward of the desired lens position, at about the tip of the contact. The contact is positioned vertically, with the tip of the fiber pointing upwardly, and an arc is passed across the end portion of the fiber, to initially heat and bulge out a location on the fiber spaced rearward of the tip. As the fiber is heated, the tip portion falls into the bulging portion, while the bulging portion moves down, with the heating continued long enough so that the tip of the molten ball of glass lies at the desired lens position.

Abstract: A system is provided for forming an end of an optical fiber into a lens, which produces a lensed fiber having an especially smooth lens surface and high strength near the intersection of the lens and the rest of the fiber. A lens is formed by establishing a pair of electrodes on opposite sides of a fiber end portion and establishing an arc between the electrode tips for a sufficient current and time to melt the fiber end portion into a lens, with the arc being repeatedly terminated and restarted at a rate of thousands of times per second.

Abstract: A method for manufacturing a flat illumination unit provides light guide channels in the form of transparent rods arranged in lines on the upper side of a plate. The upper side of a plate is coated with a casting compound and, after hardening of the casting compound, the plate is eroded from the opposite side until only the light guide channels remain respectively surrounded on three sides by the casting compound and therewith form a film.

Abstract: According to the method of the invention, molds charged with a monomer mixture are arranged into columns with precisely coaxial casting surfaces inside these columns, namely, in tubes of cylindric shape with openings only 0.01 to 0.03 mm larger the diameter of the outer cylindric surface of the mold or the diameter of a hypothetical cylindrical surface circumscribed to any other, preferably a parallel outer surface of the casting mold. The tube with the inserted column of molds is provided with airtight seals at both ends whereas at least one seal is provided with a valve for alternating evacuation and refilling with an inert gas. The invention also provides apparatus by which a complete sequence of required operations including column tilting and rotation is carried out with the tubes charged in this way until the polymerization is completed without transferring the molds from sealed tubes from one apparatus to another or into intermediate magazines.

Abstract: While polymerizing a contact lens monomer in a mold, grooves or other surface configurations are formed on the resulting polymeric lens surface by irradiating the monomer through a mask pattern which corresponds to the grooves or other desired configurations.

Abstract: A method and apparatus for making a plastic lens and a plastic lens made thereby are provided, the method comprising the steps of disposing a lens forming material comprising a liquid monomer and a photosensitive initiator into a mold cavity defined in part between a pair of spaced apart mold members each having a lens forming surface facing the cavity and an outer opposed surface, directing rays of ultraviolet light from a source thereof against the outer surface of at least one of the mold members so as to pass therethrough to act on the lens forming material in the cavity to produce the lens therefrom, and forming the outer surface of the one mold member with structure to cause the ultraviolet light directed thereagainst to be substantially evenly distributed throughout the lens forming material in the cavity in order to tend to prevent optical distortions in the lens being formed therefrom.

Abstract: The present invention relates to anhydrous crystals of maltitol and the whole crystalline hydrogenated starch hydrolysate mixture solid containing the crystals, and processes for the production and use thereof.

Abstract: A curved surface shaping apparatus has a liquid tank for developing a monomolecular film on the surface of liquid contained in the liquid tank, a jig for holding a base member to be shaped, and moving means for moving the base member held by the jig with the shaped surface of the base member intersecting the liquid surface. A curved surface shaping method comprises a step of moving a base member to be shaped relative to a liquid surface on which a monomolecular film is formed, with the liquid surface and the shaped surface of the base member intersecting each other.

Abstract: A process for the fabrication of seamless substrates which comprises (1) providing a substrate with a release coating composition thereover; (2) depositing thereon by electrostatic powder spraying a polymer; (3) melting the polymer blend; and (4) subsequently permitting the melted blend to cool. Thereafter, layered photoconductive imaging members can be prepared by the application, for example, of a ground plane, a photogenerating layer, and a charge transport layer.

Abstract: A method and apparatus for continuous processing of metal between molten and bright hot rolled stages includes the production of uniform liquid metal droplets at the top of a shot tower containing inert gas, forming and maintaining columns of closely spaced but separate metal droplets, retarding the flow of said droplets to a slow, substantially constant, velocity and cooling the droplets principally by radiation to at least partial solidification, collecting the at least partially solidified droplets in a bottomless receptacle in a weakly cohesive column, passing said column into the bite of a pair of mill rolls, rolling the said column into a rolled product, and cooling the rolled product by arc contact with off-set colling/flatening rolls and by radiation and convection cooling in an inert gas.

Abstract: Cosmetic contact lenses, which are tinted with daylight fluorescent pigments in the iris area, can change the wearer's apparent iris color to any desired color, including changing a dark iris to a lighter color such as blue or green.

Abstract: In an optical disk, a single recording layer is formed on a transparent substrate. The recording layer has an insulative base layer in which metal clusters and organic clusters are uniformly contained. When radiation is incident on the recording layer such that the intensity of the radiation is changed in accordance with the type of recording information, the metal clusters absorb radiation energy. The organic clusters produce a gas component in accordance with a level of the radiation energy absorbed by the metal clusters, thereby causing the base layer to incur a local projection by a pressure of the gas component such that a protuberance is formed on the base layer.

Abstract: Hybrid contact lenses and other composite polymeric articles of precise dimensions are made by placing a first monomer composition in a mold and irradiating and polymerizing a central portion only with ultraviolet radiation. Unpolymerized monomer is removed, a second monomer composition is placed in contact with the polymer formed from the first monomer composition and the latter is polymerized by ultraviolet irradiation or by other means to obtain a composite article which is then machined to form a hybrid lens.

Abstract: Novel, non-crosslinked copolymers of vinyl trifluoroacetate (VTA) and up to 5 weight percent of the VTA of certain comonomers, such as vinyl esters, vinyl ethers, or disubstituted ethylene monomers, are disclosed. Solvolysis of these copolymers provides novel water-insoluble, non-crosslinked, poly(vinyl alcohol) copolymers which can be hydrated to copolymers having controllably variable hydrogel properties and high strength. Such poly(vinyl alcohol) copolymers are particularly desirable as ophthalmic devices such as contact lenses, corneal implants and transplants, and intraocular lenses.