Abstract: A method of molding resin having substantial amounts of fiber and mineral fillers that provides, without the necessity of a base coat, a metallizable surface of reflector quality is possible. The method is useful for making a vehicle lamp reflector with a substantially organic skin over a substantially inorganic core. The organic skin may be metallized without using a base coat. The reflector may even be molded to give a surface gloss sufficient to be metallized without a base coat, and still meet the optical and durability requirements necessary for a vehicle headlamp.

Abstract: A process for manufacturing a non-metallic dental prosthesis including a ceramic frame and an esthetic ceramic veneer including the steps of: preparing the ceramic frame by press molding a composition comprising from 1 to 50 parts by weight glass particles and from 50 to 99 parts by weight ceramic particles at a molding temperature from 800 to 1300.degree. C.; applying a slurry comprising a dental ceramic veneering composition to the thus prepared ceramic frame; and firing the ceramic frame having the slurry applied thereto at a temperature lower than the molding temperature to produce said dental prosthesis. The dental ceramic veneering composition may have a melting point at least 50.degree. C. less than the molding temperature.

Abstract: A process for manufacturing dental prosthetics based on ceramics including the following steps:machine-processing a prefabricated shaped body to form a molded body with the patient's situation being considered, said prefabricated shaped body consisting of at least one oxide-ceramic material selected from the group consisting of aluminum oxide, magnesium oxide, zirconium oxide, and titanium oxide and minor amounts of siliceous additives;compacting the thus obtained molded body; andoptionally jacketing the compacted molded body.

Abstract: Dual axis retroreflective articles and methods of using them are disclosed. The retroreflective articles may combine dual axis retroreflection with three axis retroreflection to provide a steady glow due to the three axis retroreflective portions of the article and also provide intermittent or flashing retroreflection as the plane of retroreflection from the dual axis retroreflector passes through or near the light source. The retroreflective articles may also include dual axis retroreflective structures in combination with sparkling reflective structures, as well as dual axis retroreflective structures in combination with both three axis retroreflective structures and sparkling reflective structures. Methods of use include moving the dual axis retroreflective structures to obtain intermittent or flashing retroreflection.

Abstract: A multi-colored lens assembly is produced in a multi-station injection molding apparatus having non-indexing ejector halves and indexing cover halves. Material is shot on an unexposed illumination side of the lens assembly from valve gated nozzle drops contained in the non-indexing ejector halves thereby producing a viewing side of the lens assembly free of surface blemishes and surface stress defects. Lens assemblies are retained in the indexing cover halves by retention mechanisms provided to overlap peripherally extreme features of the lens assemblies. Lens assemblies are affirmatively released from the non-indexing ejector halves by ejection pins or blades simultaneously with parting of the mold halves.

Abstract: A process for the extrusion of plastic plates with very finely structured surface using an extrusion system which is equipped with an extruder and a three roll polishing stack containing a roller with the structuring surface. The system is designed for coextrusion and the plastic plates are produced via two extruders as a coextrudate CX from a highly viscous basic molding compound BF and a low viscosity molding compound NF which is extruded on BF. The surface of said plates is structured via the three roll polishing stack. Fresnel lenses produced by the process may be used in solar collectors.

Abstract: A method of molding resin having substantial amounts of fiber and mineral fillers that provides, without the necessity of a base coat a metallizable surface of reflector quality possible. The method is useful for making a vehicle lamp reflector with a substantially organic skin over a substantially inorganic core. The organic skin may be metallized without using a base coat. The reflector may even be molded to give a surface gloss sufficient to be metallized without a base coat, and still meet the optical and durability requirements necessary for a vehicle headlamp.

Abstract: A resin injector is used to fill recesses created in plaster moulds containing teeth in the interior of muffles with resin, with a simple economic mechanical device which is attached to the muffle and is operated by a conventional press. An assembly of two cylindrical part (4,8) is adjusted to a wide inlet mouth cut in the muffle. The resin which is received in this assembly is projected towards the muffle through at least one hole, which can be opened or closed at will by means of a manually operated part.

Abstract: A plastic molding apparatus and method employs a pair of dies having at least one cavity with a mirror surface and wherein a plastic base material which is pre-molded is inserted into the cavity and clamped by the pair of dies. The plastic base material is then heated and melted at glass transition temperature or higher so that a resin internal pressure is generated, and then the plastic base material is annealed so that the mirror surface is transferred to the plastic base material. One of the dies has a separation die in which the cavity is formed. A cavity forming portion thereof has a cavity forming surface and a cavity side board portion which is adjacent to the cavity forming portion and surrounds the cavity forming surface. A separating die clamping structure clamps the separation die from both sides so as to compress an elastic member mounted between the cavity forming portion and the cavity side board.

Abstract: In manufacturing an optical semiconductor device, light-emitting elements are mounted on their respective printed boards of an insulating plate with a silver paste interposed therebetween. A sealing mold having a shape (a lens forming portion) necessary for forming a projected lens is adhered to the major surface of the insulating plate in accordance with each of the light-emitting elements of each of the printed boards. A liquid epoxy resin having a melt viscosity of 100 Pa.multidot.s to 200 Pa.multidot.s is continuously injected into the sealing mold with the lens forming portion of the sealing mold downward. The liquid epoxy resin is then hardened to form a projected, domed lens on each of the light-emitting elements. After that, the sealing mold is removed, and the insulating plate is separated for each of the light-emitting elements into surface-mounted optical semiconductor devices each having a projected, domed lens.

Abstract: A process for producing a ceramic network material from a ceramic suspension includes casting a suspension in a tooth-shaped mold. The suspension includes dispersed alumina particles in a medium containing deionized water with a pH in a range of about 4 to 5 and a concentration of polyvinyl alcohol in a range of about 0.5 to 1% by weight. The process includes the steps of slip casting the suspension in a plaster tooth mold and drying the molded suspension to draw the water from the suspension. The dried suspension then is fired in a furnace at a temperature in a range of about 1000 to 1400.degree. C. to form a ceramic network. After the dried suspension has been fired and excess water and polyvinyl alcohol has been removed from the suspension, lanthanum aluminosilicate glass is infused to a coronal portion of the ceramic network to form a glass layer with a thickness in a range of about 1 to 2 mm within the ceramic network.

Abstract: The present invention provides light reflector component having a reflective surface of sufficiently high accuracy. As shown in FIGS. 2(a) and 2(b), an injection mold 3 used to manufacture a light reflector component of the invention includes a male half 3a and a female half 3b. A resin film 1 having a shape of light reflective surface is placed on a protrusion element 4 formed on the male half 3a of the injection mold 3 which is set in a clamp mechanism of an injection molding apparatus (not shown). After the injection mold 3 is closed, a molten resin 6 is injected into a space defined by the male half 3a and the female half 3b.

Abstract: A method of making a dental restoration is provided wherein preforms based on impressions of actual human teeth of varying sizes are employed. The method consistently yields dental restorations having excellent aesthetics and does not demand a high level of technical and artistic skill of the individual dental technician.

Abstract: A retroreflective element which may be used in pavement markings comprising a core having (a) a central layer having first and second major surfaces and at least one vertical surface, (b) a barrier layer applied to the first major surface, and (c) a barrier layer applied to the second major surface; and a plurality of optical elements embedded in the vertical surface(s) of the central layer.

Abstract: A mold 79 that includes an array of cube-corner elements 80 that are arranged in the array such that a retroreflective cube-corner sheeting 60 that is formed thereon is capable of glittering when light is incident on the sheeting. The array may be defined by three sets of intersecting grooves 25, 26, 27 where each groove set includes two or more generally parallel grooves. At least one groove in at least one of the sets has faces 22 of adjacent cube-corner elements 30a, 30b arranged such that a dihedral angle .alpha. located between adjacent faces varies along the groove(s) in the set.

Abstract: A lens body or article with lens is produced by forming lens-forming defining lines on the surface of a substrate, coating a lens-forming resin on the surface to thereby allow the lens-forming resin to swell in a convex form between the lens-forming defining lines by means of the repellency of the lens-forming resin with the lens-forming defining lines, and then curing the lens-forming resin. To this method is added a step of providing an image on the substrate to obtain an article with lens having the image. The image can stereoscopically be seen through the article with lens obtained by this method.

Abstract: A method for manufacturing an artificial tooth replacement for at least one tooth includes the step of prefabricating a ceramic reinforcement member. Connecting elements are formed at the reinforcement member for fastening the artificial tooth replacement to at least one tooth stump of a patient. The ceramic reinforcement member is covered with a ceramic cover material for completing the artificial tooth replacement.

Abstract: An optical film is provided which includes a disperse phase of polymeric particles disposed within a continuous birefringent matrix. The film is oriented, typically by stretching, in one or more directions. The size and shape of the disperse phase particles, the volume fraction of the disperse phase, the film thickness, and the amount of orientation are chosen to attain a desired degree of diffuse reflection and total transmission of electromagnetic radiation of a desired wavelength in the resulting film.

Abstract: Retroreflective material is disclosed which is formed of an array of microprisms which reflect light more uniformly by forming a concave curvature in the base face of the prisms.

Abstract: A shaped article, specifically an artificial tooth, is made of two parts. individually shaped first part 18, specifically the head part or superstructure of the artificial tooth, has a standardized locking portion 26 for engagement with a standardized counter-locking portion 24 provided on a pre-fabricated second part 16, specifically the shaft part of the tooth to be implanted in a patient's jaw. The individually shaped part 18 is manufactured by using a pre-fabricated sonotrode 38 for producing the configuration of the locking portion 26 and one or more individually produced shaping sonotrodes 44 are used for generating the parts of the surface other than the locking portion 26. This permits the individually shaped part to be produced in an economic way yet with high precision of the locking portion.

Abstract: A retroreflective sheeting having a multiplicity of discrete, cube-corner elements cured in situ on a transparent, polymeric overlay film deformed into a three-dimensional structure so that base edges of a plurality of cube-corner elements are non-planar with respect to one another. The retroreflective article preferably has at least one target optical property. The present invention is also directed to a method of deforming the retroreflective sheeting to form a retroreflective article in which the base edges of a plurality of cube-corner elements are non-planar with respect to one another.

Abstract: A cube corner article and method of manufacturing the article from a series of unitary substrates. A plurality of pins are assembled to form a mold having an array of cube corner elements on a surface. Then, a replica of the cube corner element array is produced in a substrate suitable for forming retroreflective surfaces. Portions of the replica substrate material are removed. The removal of these portions forms at least one cavity bounded by side walls in the replica at a depth at least that of the cube cube corner elements. The replica is replicated to produce an additional directly machinable substrate suitable for forming retroreflective surfaces having at least one raised section having sidewalls at a height at least that of the cube corner elements. At least one raised section is directly machined to form an array of cube corner elements.

Abstract: An injection molding process for the manufacture of composite, molded, thermoplastic articles comprising an insert member contiguous with a second body of molded thermoplastic material, is carried out in a mold assembly comprising a core member and a cavity member engageable therewith. The core and cavity members cooperate to define a first molding station having a first cavity for molding an insert member, and a second molding station which is configured to receive and support an insert member therein, and to provide a second molding cavity contiguous with the insert member for molding a thermoplastic body contiguous with the insert. At the start of the process, an insert is supported in the second station, and thermoplastic materials are injected into the molding cavities in the first and second stations so as to mold an insert and a completed, composite member.

Abstract: A semi-transmissive semi-reflective film laminate consisting of a semi-transmissive semi-reflective layer and a film, the semi-transmissive semi-reflective layer being set on the film, characterized in that the semi-transmissive semi-reflective layer contains pearl pigment and a light transmissive resin, the average of the angles of orientation of the pearl pigments being less than 30.degree., the film is a film selected from the group consisting of a support body having a vacant space internally and a polarizing film.

Abstract: A method of forming a light weight, closed-back mirror. The mirror is formed as a monolithic construction by the use of chemical vapor deposition techniques. A first deposition forms sheets of the material, which are machined to the proper size to form reinforcing ribs. A sacrificial mandrel is formed with grooves to receive the ribs in their assembled positions. The upper surface of the mandrel is in proximity to the rear edges of the ribs to form a substantially continuous surface. The mandrel and ribs are then subjected to a chemical vapor deposition process which forms a first coating upon the outer face of the mandrel, forming a back plate and side wall. The mandrel is then turned over, and the base is removed by machining to expose the front edges of the ribs. This process leaves islands of mandrel material between the ribs to form a substantially continuous surface. The mandrel and ribs are then subjected to a chemical vapor deposition process.

Abstract: A method is disclosed for the production of a molded article, using a mold assembly including a mold having a cavity, for producing a molded article from a thermoplastic resin; an insert block formed of ceramic or glass having a thermal conductivity of 2.times.10.sup.-2 cal/cm.sec..degree.C. or less, the insert block being disposed inside the mold, constituting part of the cavity, and having a thickness of 0.5 mm to 10 mm; and a cover plate for covering a peripheral portion of the insert block. The cover plate is attached to the mold and constitutes part of the cavity, wherein a clearance between the insert block and the cover plate is 0.001 mm to 0.03 mm, an amount of overlapping of the insert block and the cover plate is at least 0.1 mm. The method includes filling a molten thermoplastic resin in the cavity, and then cooling the thermoplastic resin to solidness.

Abstract: A dental restoration part is produced from a ceramic material by a method ultrasonic working. The method includes forming a negative mold from a master sonotrode, forming a pre-working sonotrode from the negative mold, and ultrasonically working a workpiece using the pre-working sonotrode. The master sonotrode is then used to ultrasonically work the workpiece to form the dental restoration part.

Abstract: Production of precision reflective mirror surfaces on low cost, lightweight molded plastic substrates (10). The process involves making a master pattern (12) having a precision machined contoured surface (13) corresponding to the precision mirror surface desired on the plastic substrate. A release layer (14) and a reflective layer (17) are applied to the master pattern and then transferred to the molded plastic substrate (10), with a curable replication layer (18) therebetween preferably comprising a filler-reinforced polymer composition which is compatible with the polymeric substrate and has a low coefficient of thermal expansion (CTE) which closely matches the CTE of the substrate. The replication layer (20) is cured to replicate the precision of the surface (13) of the master pattern (12), which can be reused to produce a multiplicity of high precision molded plastic mirrors (21).

Abstract: A process for producing ceramic dental prostheses, with which ceramic dental prostheses may be produced in the same diversity of shapes and with the same accuracy as metal dental prostheses. The process includes shaping an unfinished piece made out of 92.1 to 93.5 wt. % zirconium oxide, 4.5 to 5.5 wt. % yttrium oxide, 1.8 to 2.2 wt. % hafnium oxide, and reworking the piece to form a dental prosthesis by means of a rotating tool made of metal-bonded diamond grains.

Abstract: The present invention provides an addition-curable composition containing an inorganic, organic or organometalic compound of palladium in an amount effective to reduce the amount of hydrogen gas evolved in the reaction of the composition. A preferred embodiment is a dental impression material composition comprising: (a) an addition-curable compound; (b) a crosslinker; (c) a platinum-containing catalyst; and (d) a palladium compound. This generally provides a positive gypsum model of, for example, a dental impression that is substantially free of pits.

Abstract: A lighting fixture includes a grating of discontinuities that is integrally molded in a translucent member for spatially modulating light from a light source of the fixture. A translucent lens forms an outer envelope portion of the fixture, the grating being mounted between the light source and the lens. A reflector mounted opposite the light source from the grating enhances light transmission through the grating. A semi-reflective shell member in front of the light source, used alone or in combination with a geodesicly segmented reflector opposite the light source, greatly enhances the visual effects of the fixture by projecting multiple images of the light source through the grating.

Abstract: A retroreflective structure has a window side and a facet side. The facet side has a plurality of steps with treads and risers intersecting at an angle. The risers include an array of retroreflective elements. Preferably, the elements are cube-corner prisms. The method includes forming the structure by polymerizing a polymerizable material in a mold having a facet side including a tiered structure having a plurality of steps with treads and risers intersecting at an angle and wherein the risers include an array of retroreflective elements.

Abstract: A process for the extrusion of plastic plates with very finely structured surface using an extrusion system which is equipped with an extruder and a three roll polishing stack containing a roller with the structuring surface. The system is designed for coextrusion and the plastic plates are produced via two extruders as a coextrudate CX from a highly viscous basic molding compound BF and a low viscosity molding compound NF which is extruded on BF. The surface of said plates is structured via the three roll polishing stack. Fresnel lenses produced by the process may be used in solar collectors.

Abstract: A retroreflective structure is described in which an array of free-standing retroreflective prisms is formed on a suitable substrate for application of the structure to pre-existing structure formed of compatible fabrics, such as tarpaulins.

Abstract: A method for producing a semiconductor device according to the present invention includes the steps of: disposing a functional element in each cavity of a multi-cavity circuit board, the multi-cavity circuit board having a number of cavities opening upward; overlaying a sealing resin sheet with a predetermined thickness containing, as a sealing resin, one of a thermoplastic resin and a thermosetting resin which is melted by heating and is cured by further heating on the multi-cavity circuit board so as to cover all of the cavities thereof; heating and pressurizing the sealing resin sheet on the multi-cavity circuit board so that the sealing resin sheet is melted to be filled in each of the cavities; and curing the molten resin filled in each of the cavities.

Abstract: A method of producing a microstructure bearing article that includes the steps of molding the microstructure on the base, curing the resin that forms the microstructure, and heat treating the microstructure. The heat treating is performed at a temperature that is at least equal to a normal glass transition temperature of the resin. The heat treating raises the glass transition temperature of the resulting polymer above approximately 333.degree. K. such that groove tip impression is reduced. Such articles are useful in backlit displays which are useful in computers and the like.

Abstract: A headlamp assembly comprising a reflector defining an open front end, a lens adapted to close the open front end of the reflector to form a lamp chamber, a bulb mounted in the lamp chamber, and a mounting structure. The reflector and lens define respective annular flange portions which are seated together at an interface and the mounting structure is formed as an injection molding including an annular main body housing portion surrounding the reflector and an annular seal portion at the inner periphery of the main body portion encapsulating the seated together flange portions so as to seal the interface between the flange portions and seal the lamp chamber. Sealing of the lamp chamber is further facilitated by the provision of a series of annular grooves in the reflector flange portion and a series of annular ribs in the lens flange portion sized to fit in the respective annular grooves in the reflector flange portion.

Abstract: A method of replicating an optically flat surface includes providing a plastic optical element having a machined flat surface. The machined flat surface includes a plurality of ridges thereon. A coating material is applied to an optically perfect flat and the optical element is rolled and positioned on the coating material applied to the optically perfect flat such that grooves between the ridges with the coating material. The coating material sandwiched between the optical element and the optically perfect flat is cured and the optically perfect flat is removed from the cured coating material.

Abstract: An optoelectronic device is fabricated by casting a transparent polymeric body surrounding an electronic component. A reflective layer is formed over the polymeric body. The reflective layer acts as a mirror to reflect light emitted by one electronic component to another electronic component which receives the light. By casting the polymeric body, a consistent and defined shape for optical transmission is provided for forming the shape of the reflective layer.

Abstract: In an aging device used to manufacture a plastic molded product, injecting and aging processes are separated from each other. Namely, a plastic base material is approximately processed in advance in a final shape by injection molding. Thereafter, the plastic base material is inserted into an aging die having plural cavities and attached to a press machine such that the aging die is clamped and opened. Next, the plastic base material is heated and melted until a temperature equal to or higher than a glass transition point so as to generate an internal resin pressure. Next, the plastic base material is gradually cooled to transfer a mirror face thereto. The aging device has a die cooling device having plural heat pipes for cooling the die and has a die heating device having plural heaters for heating the die. The heat pipes and the heaters are arranged in a die plate of the press machine.

Abstract: A lens/mirror tower (LMT) of a multiple-disk array, optical storage system includes a plurality of lens and mirror elements integrally formed on a monolithic, optically-clear substrate. There is a specific lens/mirror set for each recording disk surface of the optical storage device; however, the mirror elements are preferably configured as one reflective surface of the substrate. The lenses are molded onto the opposite surface in a single operation that fixes their relative positions. The LMT is generally fabricated using a lens replication process. Initially, a glass substrate is formed with a trapezoidal configuration. A lens array mold is also formed with a plurality of cavities arranged in overlapping pairs. The cavities are filled with optical-quality resin and the mold is applied to the surface of the substrate opposing the reflective angular, e.g., 45.degree., surface. Once cured, the resin serves as an array of lenses that are aligned with the optical paths to the objective lenses of the disk array.

Abstract: A resin polygonal mirror having reflective facets each of which is made by injecting resin from a plurality of pin point gates or a single film gate. A core of the polygonal mirror is made of a different resin from the resin which is the material of the reflective facets. A mold of the polygonal mirror has side segments which are divided by parting lines extended from corners of the reflective facets.

Abstract: The artificial tooth blanks made by series production involve a dentin-colored fired dental ceramic composition including a previously compression-molded hard core and optionally a retention, wherein the size of the artificial tooth blank is reduced over that of the corresponding finished artificial tooth and the artificial tooth blanks do not contain an enamel layer. The retention may involve one or more high-melting shells incorporated by firing and containing high-melting retention pins soldered therein after firing, wherein the retention pins as well as the solder are stable under the melting conditions for dental ceramic compositions for bridges and crowns, and especially so in the presence of air as well.

Abstract: A method of manufacturing artificial tooth veneer restorations for natural teeth composed of a ceramic core by pressing and sintering ceramic powder. The core is preferably manufactured from a high strength densely sintered ceramic material by copy milling from an impression of the prepared tooth surface to a compacted body, a presintered body or a sintered body. Alternatively, the core is manufactured by compacting the ceramic powder against a body, which surface is copy milled from a model of the prepared tooth surface. During the copy milling, the sintering shrinkage is considered by enlargement of that body. The tooth veneer restorations are given their final shape by shaping the external surface of the compacted, presintered or sintered ceramic body. After the final sintering, the external surface can be shaped before a veneer material is attached to the external surface of the core by firing of dental porcelain.

Abstract: Spacers or wedges are disclosed for use in combination with mold elements such as lens and/or reflex reflector pins in a pin block or matrix assembly. Such assemblies are used in the manufacture of molds for producing, for example, front and/or rear light units for motor vehicles. The wedges or spacers are selectively located between rows or banks of reflex or optic pins to provide required orientation to selected groups of the pins so that the necessary reflectivity of the finished product is provided in the curved portion thereof.

Abstract: A method and apparatus for forming "seamless" retroreflective sheeting is described. At least two mold surfaces are used, each having alternate areas of arrays of prism recesses and spaces. In a first step, prisms are formed in one of the mold surfaces and applied to a base film or web. Next, prisms are formed on the second mold surface and applied to the spaced areas left in the first step.

Abstract: Light reflective buttons according to this invention are made from a plurality of fused strata, the top stratum having an exposed reflective area, preferably of pleochroic or dichroic material in a plane. Manufacture of the buttons involves stacking the top stratum with the reflective area exposed on top of a sub-stratum, and then heating the complex to a temperature sufficient to fuse the stack. During fusion, the stack forms a dome with a flat base. Sub-strata may be added to the stack as needed prior to heating for strength and/or aesthetic purposes. Preferably the strata are all glass, with the top stratum being a cut or otherwise shaped piece of sheet glass commonly known as "dichroic glass." For a reflective area comprised of a plane of pleochroic or dichroic crystalline material, the temperature at which fusion of the strata occurs is too low to melt the crystalline plane, and so it is substantially unaffected by the heating.

Abstract: An article and method for making a plastic molded optoelectronic interface are provided. A leadframe having a first segment and a second segment with the first segment having a first tab and the second segment having a second tab is provided. The first and the second tabs extend away from the first segment and the second segment, respectively, and toward each other. The first segment and the second segment are positioned in a parallel configuration with the first and second tabs pointing toward each other. A first optical portion having a reflective surface with an angle is formed between the first tab of the first segment and the second tab of the second segment. A second optical portion that surrounds the first optical portion is formed.

Abstract: A homogenizer for incident light including: a sheet of embossable material including a one micro-sculpted surface relief structure that (i) controls the direction in which light propagates and (ii) homogenizes light with directionality has been formed by replicating in the sheet of embossable material another micro-sculpted surface structure that (i) controls the direction in which light propagates and (ii) homogenizes light with directionality, the another micro-sculpted surface structure having been formed in a photosensitive medium having a refractive index by: (a) generating random, disordered and non-planar speckle in the photosensitive medium using coherent light, the coherent light having been diffused through a holographic diffuser, so as to define non-discontinuous and smoothly varying changes in the refractive index of the photosensitive medium, the smoothly varying changes scattering collimated light into a controlled pattern with smooth brightness variation; and (b) developing the photosensitive m

Abstract: A deflection mirror tower (DMT) of a multiple-disk array, optical storage system includes a plurality of prism members, each having an angular mirror surface, arranged along a vertical axis of the DMT and configured at a predetermined angular orientation to deflect a laser beam to a respective disk surface. The DMT is generally fabricated using a two-level partitioning process. Several prepared glass substrates, i.e., one for each mirror type, are initially sliced into bars having predetermined geometries. A bar from each substrate is sequentially aligned to a master reference and bonded to adjacent bars to form an intermediate bar stack. The stack is then segmented into a plurality of DMT components, each having a plurality of prism members.