Changing Mold Size Or Shape During Molding Or With Shrinkage Compensation Patents (Class 264/2.2)
  • Patent number: 6759182
    Abstract: There is provided a manufacturing method of an optical device having a micro-asperity pattern that has various kinds of accurate three-dimensional shapes and is realized as thin films. A substrate is coated with a resin thin film made of a photosensitive resin, and the temperature of the resin thin film is controlled so as to be lower than the photosensitivity extinction temperature of the resin thin film. A micro-asperity pattern of a stamper is pressed against the resin thin film when the resin thin film is in a softened or melted state by pressurizing means, whereby a micro-asperity pattern is formed on the surface of the resin thin film.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: July 6, 2004
    Assignee: Omron Corporation
    Inventors: Masaaki Ikeda, Akihiro Funamoto, Motohiko Matsushita, Shigeru Aoyama
  • Patent number: 6755996
    Abstract: A process for forming a preform for use in compression molding an optical lens is provided. A heated reservoir desirably a thermoplastic extruder is filled with a thermoplastic material. The heated reservoir has a fluid outlet which is located in close proximity to the concave mold. The thermoplastic material, for example, polycarbonate pellets is fluidized in the heated reservoir. A predetermined amount of a fluid thermoplastic material is dispensed from the reservoir outlet onto the outside the edge of a heated concave mold prior to the fluid solidifying so that the fluid makes point or line contact as it first contacts the concave molds. The fluid flows down the sloping wall of the concave mold into the concave mold and forms a blob of material having a greater thickness at the center of the concave mold than at the periphery of the mold. The thermoplastic blob is then allowed to cool below its melting temperature.
    Type: Grant
    Filed: July 13, 2001
    Date of Patent: June 29, 2004
    Assignee: Chrysalis Development Company LLC
    Inventor: Martin Greshes
  • Patent number: 6716374
    Abstract: An injection-compression molding apparatus includes a stationary mold provided with a nozzle for injecting molten resin, and a movable mold driven by a servo motor. In compressing the resin, high-speed position control of the movable mold is first performed, which is then switched to speed feedback control which enables delicate regulation of clamping pressure in accordance with pressure fluctuations in the resin.
    Type: Grant
    Filed: March 27, 2001
    Date of Patent: April 6, 2004
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hiroshi Yutani, Shinji Kadoriku, Akira Yabe, Tadao Murata, Ryoma Murase
  • Patent number: 6705725
    Abstract: A method of producing an optically molded product of a thermoplastic resin by injection compression molding, the method comprising the steps of: (1) expanding the volume of a cavity more than the volume of the optically molded product of interest; (2) injecting a molten thermoplastic resin into the cavity through an injection cylinder; (3) compressing the expanded cavity to a prescribed thickness of the molded product; (4) returning an excess of the thermoplastic resin produced by the compression into the injection cylinder; and (5) keeping the molten thermoplastic resin in the cavity until the molded product of interest is formed. The present invention makes it possible to produce an optically molded product (for example, a spectacle lens) free from a weld line and excellent in surface accuracy using a metal mold having a simple structure industrially advantageously.
    Type: Grant
    Filed: May 20, 2003
    Date of Patent: March 16, 2004
    Assignee: Teijin Chemicals, Ltd.
    Inventors: Kiyohito Gotoh, Hiromi Ichioka
  • Patent number: 6703100
    Abstract: A recording medium for information signals including a substrate, a signal recording layer provided on one major surface of the substrate and a clamp member having a positioning unit at its center portion and formed of a material that can be magnetically attracted by a magnet. The clamp member is unified to the center portion of the substrate so that the surface of the clamp member will be flush with the substrate surface.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: March 9, 2004
    Assignee: Sony Corporation
    Inventors: Nobuyuki Arakawa, Ken Minemura, Yuji Akiyama, Toshiyuki Kashiwagi
  • Publication number: 20040021238
    Abstract: A method for making an organic glass lens or lens blank which comprises providing a two-piece mold defining a molding cavity having a vertical axis which is part of a fixed reference system comprising said vertical axis and a horizontal axis which intersects at the center of the mold, a liquid tight annular closure member disposed at the periphery of the mold pieces for maintaining the two mold pieces and closing the molding cavity, wherein the annular closure member comprises at least a portion thereof made of a material that is initially gas permeable but becomes gas impermeable when in contact with a liquid polymerizable composition.
    Type: Application
    Filed: August 5, 2002
    Publication date: February 5, 2004
    Applicant: Essilor International Compagnie Generale d'Optique
    Inventors: James A. Reed, Joseph Boryslawski
  • Publication number: 20030201555
    Abstract: A method of producing an optically molded product of a thermoplastic resin by injection compression molding, the method comprising the steps of:
    Type: Application
    Filed: May 20, 2003
    Publication date: October 30, 2003
    Inventors: Kiyohito Gotoh, Hiromi Ichioka
  • Patent number: 6638451
    Abstract: The invention is concerned with the problem that with known plastic casting molds, especially those of polypropylene, the lenses produced with these molds have a slippery surface. The invention solves this problem through the use of polymers which are notable for their very low oxygen permeability.
    Type: Grant
    Filed: August 25, 2000
    Date of Patent: October 28, 2003
    Assignee: Novartis AG
    Inventors: Peter Hagmann, Axel Heinrich, Willi Hoerner, Robert Allen Janssen, John Martin Lally, Robert Earl Szokolay, Bernhard Seiferling
  • Patent number: 6616868
    Abstract: A method of producing an optically molded product of a thermoplastic resin by injection compression molding, the method comprising the steps of: (1) expanding the volume of a cavity more than the volume of the optically molded product of interest; (2) injecting a molten thermoplastic resin into the cavity through an injection cylinder; (3) compressing the expanded cavity to a prescribed thickness of the molded product; (4) returning an excess of the thermoplastic resin produced by the compression into the injection cylinder; and (5) keeping the molten thermoplastic resin in the cavity until the molded product of interest is formed. The present invention makes it possible to produce an optically molded product (for example, a spectacle lens) free from a weld line and excellent in surface accuracy using a metal mold having a simple structure industrially advantageously.
    Type: Grant
    Filed: October 19, 2000
    Date of Patent: September 9, 2003
    Assignee: Teijin Chemicals, Ltd.
    Inventors: Kiyohito Gotoh, Hiromi Ichioka
  • Publication number: 20030164564
    Abstract: The invention relates to a method and apparatus for making thick-walled plastic parts, in particular blanks for optical lenses. In accordance with the invention, a two-phase production process is proposed in order to make thick-walled lenses with high optical quality and homogenous material properties, wherein in a first phase, a thin lens is first made through injection molding, and in a second step the lens is enlarged, i.e. “inflated”, until the final thickness through continued injection of plastic material.
    Type: Application
    Filed: March 31, 2003
    Publication date: September 4, 2003
    Applicant: KRAUSS-MAFFEI KUNSTOFFTECHNIK GMBH
    Inventor: Bernd Klotz
  • Patent number: 6592785
    Abstract: An optical component molding device and method is disclosed. The molding device includes a heating section, a heating/pressing section, and a cooling section. A carrying member sequentially conveys molding units between these treatment sections. Either the molding units or the carrying member is provided with coded information pertaining to the treatment each molding unit is to receive. A sensor scans the coded information and relays it to a master control unit that controls the operation of the various sections. The device automatically accommodates different height molds, as well as allows for different length pressing strokes, as well as different pressures, temperatures and rates of heating and cooling, and different durations of pressing to be individually controlled for each mold unit.
    Type: Grant
    Filed: March 24, 2000
    Date of Patent: July 15, 2003
    Assignee: Fuji Photo Optical Co., Ltd.
    Inventor: Katsunori Mukasa
  • Publication number: 20030127757
    Abstract: A method for the injection moulding of a plastic article, such as a CD or DVD comprises the following steps: the provision of a mould (1) having at least two mould parts (2, 3), the provision of positioning means (9, 22) for positioning the mould parts (2, 3) with respect to one another a nominal distance apart such that a mould cavity (6) is obtained, injecting a fluid material (26) into the mould cavity under pressure, influencing the positioning means (9, 22) in such a way that the nominal mutual spacing of the mould parts is maintained when injecting the material (26) into the mould cavity (6) under pressure.
    Type: Application
    Filed: November 8, 2002
    Publication date: July 10, 2003
    Inventors: Ronaldus Johannes Cornelis Maria Kok, Michael Adrianus Theodorus Hompus, Marinus Franciscus Johannes Evers
  • Publication number: 20030111749
    Abstract: For each lens molding cycle, the method comprises the following steps:
    Type: Application
    Filed: December 17, 2001
    Publication date: June 19, 2003
    Inventors: Hao-Wen Chiu, Hsinjin Yang
  • Publication number: 20030030160
    Abstract: A system for molding optical attenuators that have a lens portion and a supporting portion includes a molding machine containing a mold, an extractor robot and optical inspection portion, and a controller that assesses the inspection information and send control signals to the molding machine and mold. The mold includes a cavity and a core which define a space in which the supporting portion and the attenuator are formed. The cavity and core are separable from each other by an actuating motor of the molding machine subsequent to each injection cycle to permit removal of each molded optical attenuator. The mold also includes a core pin, movably located in the core element. The core pin has a proximal end defining a surface of the lens portion and a distal end remote from the molding space. A core pin motor is coupled to the core pin, through a number of intermediate elements, so that the core pin can be moved relative to the core element to adjust a thickness of the lens portion.
    Type: Application
    Filed: October 1, 2002
    Publication date: February 13, 2003
    Inventors: Ricky W. Tumlin, J. Larry Underwood
  • Patent number: 6500376
    Abstract: A method of injection molding a layered plastic component includes providing a sealing structure around the periphery of a mold cavity formed between first and second mold halves to contain plastic material in the cavity during injection. The first and second mold halves are closed to a first gap therebetween. A first plastic material is injected into the cavity. The first and second mold halves are closed together to a full closure position to compress the first plastic material. The first and second mold halves are held together for a period of time sufficient to partially solidify the first plastic material. The first and second mold halves are opened to a second gap therebetween, and at least one stop member is moved into position between the first and second mold halves.
    Type: Grant
    Filed: January 27, 2000
    Date of Patent: December 31, 2002
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Craig William Pack, Ronald Dennis Polley
  • Publication number: 20020163095
    Abstract: This invention relates generally to opthalmic molds and methods useful for casting opthalmic moldings. In one aspect, the invention relates to a mold for casting an opthalmic molding formed from a first mold half detachably affixed to a second mold half, whereby the mold has a top and a bottom; and a cavity formed by the first and second mold halves, wherein the cavity receives a lens forming material through an opening at the bottom of the mold and vents gas and excess lens forming material from an opening at the top of the mold. In another aspect, this invention relates to methods for casting opthalmic moldings, particularly intraocular lenses.
    Type: Application
    Filed: March 15, 2002
    Publication date: November 7, 2002
    Inventors: Rafael Victor Andino, Tracy Weldon, Richard Charles Turek
  • Patent number: 6475410
    Abstract: A method and apparatus for producing a contact lens material having two opposite lens-forming surfaces is disclosed. A first resin mold having a molding surface providing one of the opposite lens-forming surfaces of the contact lens material is injection-molded by closing a first and a second die to define at least one mold cavity and injecting a resin material into the mold cavity. A second resin mold having a molding surface is injection-molded by closing a third and a fourth die to define at least one mold cavity and injecting a resin material into the second mold cavity. The dies are separate away from each other and molding material is introduced into one of the resin molds which are held on one of the respective dies. The dies holding the first and second resin molds are moved relative to each other to assemble the first and second resin molds to define a mold cavity for the contact lens material.
    Type: Grant
    Filed: April 9, 2001
    Date of Patent: November 5, 2002
    Assignee: Tomey Corporation
    Inventor: Makoto Nakagawa
  • Publication number: 20020140117
    Abstract: A mold assembly for producing a plurality of contact lenses includes a front curve fixture assembly, a base curve fixture assembly and a plurality of mold cavities. The plurality of mold cavities are defined by a surface on either the front or the base curve fixture assembly and is disposed in a zig-zag manner relative to each other. Each of the plurality of mold cavities includes a retention edge for complimentary engagement with a mold. The retention edge of a first subset of the plurality of mold cavities is spaced apart from a selected fixture mating surface at a first distance and the retention edge of a second subset of the plurality of mold cavities being spaced apart from the selected fixture mating surface at a different second distance so that a plurality of molds may be placed in adjacent cavities so as to overlap the mold flanges.
    Type: Application
    Filed: March 26, 2002
    Publication date: October 3, 2002
    Inventors: Todd A. Russell, Alan Conley
  • Publication number: 20020125588
    Abstract: There is provided a manufacturing method of an optical device having a micro-asperity pattern that has various kinds of accurate three-dimensional shapes and is realized as thin films. A substrate is coated with a resin thin film made of a photosensitive resin, and the temperature of the resin thin film is controlled so as to be lower than the photosensitivity extinction temperature of the resin thin film. A micro-asperity pattern of a stamper is pressed against the resin thin film when the resin thin film is in a softened or melted state by pressurizing means, whereby a micro-asperity pattern is formed on the surface of the resin thin film.
    Type: Application
    Filed: March 6, 2002
    Publication date: September 12, 2002
    Inventors: Masaaki Ikeda, Akihiro Funamoto, Motohiko Matsushita, Shigeru Aoyama
  • Patent number: 6440335
    Abstract: Disclosed are novel molding methods for injection molding thermoplastic lens elements and particularly adapted for the manufacture of steeply curved and/or thin-centered lenses.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: August 27, 2002
    Assignee: Sola International, Inc.
    Inventors: Jeffrey M. Kingsbury, Robert H. Juul, Michael J. Tuhtan, Martin D. Rolph, Michael A. Morris, Colin M. Perrott, Simon J. Edwards, Ray S. Spratt
  • Patent number: 6433936
    Abstract: Disclosed is a lens of gradient dielectric constant and methods for the production of same. The lens includes an inner core comprising a cured or fused substantially homogenous blend of glass spheres, curable or fusible binder and, as needed to increase dielectric constant, a low-loss dielectric material. The inner core preferably has a dielectric constant of about 2.0, and an interstitial void volume (representing trapped air space between elements of the cured or fused material) of from about 30% to about 50%. The lens also includes an outer shell layer comprising a cured or fused substantially homogenous blend of hollow glass spheres and curable or fusible resin. The outer shell layer preferably has a dielectric constant of about 1.0, and an interstitial void volume of from about 30% to about 50%. In addition, the lens includes a minimum of one, and preferably two or more intermediate layers, the intermediate layers having a dielectric constant falling between 1 and 2.
    Type: Grant
    Filed: August 15, 2001
    Date of Patent: August 13, 2002
    Assignee: Emerson & Cuming Microwave Products
    Inventors: Michael P. Carpenter, Mary M. Osward, David A. Gibbs
  • Patent number: 6398988
    Abstract: A rear signal lamp of an automotive vehicle comprising a lamp housing and a curved cover lens for enclosing a thin light managing system. The thin light managing systems includes a plurality of backlight light-emitting diodes mounted in a light mounting substrate and secured to the lamp housing. A control module operatively connected to the light-emitting diodes for controlling the operation and illumination of the light-emitting diodes. A reflector matrix having a plurality of reflector cones corresponding to each of the light-emitting diodes in the mounting substrate and a hybrid optics panel having a direct lensing section covering the reflector matrix and light-emitting diodes and a double redirecting light pipe section surrounding the lensing section. A single light-emitting diodes is coupled along spaced apart quadrants of the redirecting light pipe.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: June 4, 2002
    Assignee: Decoma International Inc.
    Inventors: David Jenkins, Robert Pagano, Kevin Garcia, Robert Passera, Joseph A. Griffin, Gerhard F. Hirmer
  • Publication number: 20020050658
    Abstract: A method for manufacturing a synthetic resin thermoplastic ophthalmic lens by injecting a thermoplastic material immediately adjacent to each side of a light polarizing wafer situated within a mold cavity. The light polarizing wafer includes tab appendages which are positionable into registration notches in the mold cavity in order to maintain the wafer in a desired position in the mold during lens formation. The thermoplastic material is then injected around the light polarizing wafer, whereupon a compression procedure is implemented where the contents of the mold cavity are compressed. The mold cavity is compressed to a predetermined position to achieve a desired shape of the lens. Uniform compression is exerted over the entire surface of lens during the compression procedure, resulting in all stresses being uniformly distributed over the lens surface to significantly negate stress-inducted birefringence in the formed ophthalmic lens.
    Type: Application
    Filed: September 10, 2001
    Publication date: May 2, 2002
    Inventor: David A. Richard
  • Publication number: 20020047220
    Abstract: An apparatus and method for filling a mold for casting optical lens. Two molding shells and a closure member form a mold with a molding cavity. To fill the mold a fluid lens-forming material is introduced into the molding cavity through a casting opening formed in the closure member. Air is venting out during the filling process through a venting opening also formed in the closure member. Both the casting opening and the venting opening are located in the upper portion of the molding cavity but spaced apart from each other at an acute angle.
    Type: Application
    Filed: August 23, 2001
    Publication date: April 25, 2002
    Applicant: Technology Resource International Corporation
    Inventor: Kai C. Su
  • Publication number: 20020038916
    Abstract: A method for molding and aligning microstructures on a patterned substrate using a microstructured mold. A slurry containing a mixture of a ceramic powder and a curable fugitive binder is placed between the microstructure of a stretchable mold and a patterned substrate. The mold can be stretched to align the microstructure of the mold with a predetermined portion of the patterned substrate. The slurry is hardened between the mold and the substrate. The mold is then removed to leave microstructures adhered to the substrate and aligned with the pattern of the substrate. The microstructures can be thermally heated to remove the binder and optimally fired to sinter the ceramic powder.
    Type: Application
    Filed: October 5, 2001
    Publication date: April 4, 2002
    Applicant: 3M Innovative Properties Company
    Inventors: Raymond C. Chiu, Timothy Lee Hoopman, Paul Edward Humpal, Vincent Wen-Shiuan King, Kenneth R. Dillon
  • Publication number: 20020036360
    Abstract: An injection compression molding method for injecting and compressing molten resin to obtain molding product using a molding die internally having a lens-forming cavity includes a pair of relatively movable inserts; a gate; a runner; and a sprue. The molten resin is injected and filled into the cavity and volume of the cavity is reduced by moving one insert toward the other insert after a time period prior to completion of injecting and filling the molten resin. At the time, a gate shut pin is protruded into the gate in synchronization with the movement of the insert to gradually close the opening of the gate. Accordingly, two demands, i.e. lower resistance in filling the cavity with the molten resin and shutting in the molten resin after the molten resin is packed in the cavity, can both be satisfied. This improves productivity and enables the production of mold products having highly accurate configuration and high quality.
    Type: Application
    Filed: November 30, 2001
    Publication date: March 28, 2002
    Applicant: Hoya Corporation
    Inventor: Tatsuo Nishimoto
  • Publication number: 20020027303
    Abstract: A method of manufacturing an optical element is disclosed which comprises the steps of providing a molding material onto a mold; giving a local temperature difference to an interface between the mold and the molding material to separate the mold and the molding material from each other in an area; and successively enlarging the area of separation made by the temperature difference to entirely separate the mold and the molding material from each other.
    Type: Application
    Filed: August 14, 2001
    Publication date: March 7, 2002
    Inventor: Masaaki Nakabayashi
  • Publication number: 20010045676
    Abstract: A method of forming a contact lens within a mold is provided. A coating of a polyionic material(s) is applied to the mold before forming a lens therein. The coating can be applied by spraying or dipping the mold within a solution(s) of polyionic materials. Various other additives can also be applied to the mold. The coating can then be transferred to a contact lens formed within the mold such that the resulting lens has altered surface properties.
    Type: Application
    Filed: January 31, 2001
    Publication date: November 29, 2001
    Inventors: Lynn Cook Winterton, Yongxing Qiu, John Martin Lally, Paul Clement Nicolson
  • Publication number: 20010038157
    Abstract: An injection-compression molding apparatus includes a stationary mold provided with a nozzle for injecting molten resin, and a movable mold driven by a servo motor. In compressing the resin, high-speed position control of the movable mold is first performed, which is then switched to speed feedback control which enables delicate regulation of clamping pressure in accordance with pressure fluctuations in the resin.
    Type: Application
    Filed: March 27, 2001
    Publication date: November 8, 2001
    Inventors: Hiroshi Yutani, Shinji Kadoriku, Akira Yabe, Tadao Murata, Ryoma Murase
  • Patent number: 6304387
    Abstract: The invention proposes a method of predicting the curvature radius of the microlens. By adjusting a spin speed of spin coating and exposure energy during a photolithography step, a volume of the patterned microlens material layer is controlled. Then a lens-forming step is performed to transform the patterned microlens material layer into a microlens. After measuring a diameter of the microlens, the volume of the microlens material layer is multiplied by a contraction coefficient to calculate a volume of the microlens. Then the diameter and the volume of the microlens are used to calculate a curvature radius.
    Type: Grant
    Filed: May 19, 2000
    Date of Patent: October 16, 2001
    Assignee: United Microelectronics Corp.
    Inventors: Chi-Fa Ku, Jeenh-Bang Yeh
  • Patent number: 6290882
    Abstract: Hard to fill large-surface-area parts and/or thinwalled configurations of optical lenses and reflective optical elements are among the difficult-to-mold thermoplastic products which require precision replication of the molding surfaces, in micro detail. We combine multiple opposing gates (to reduce the meltflow pathlength) with non-isothermal steps of firstly, heating these mold surfaces (with circulating heat transfer fluids supplied by a hot side supply system, to a temperature setpoint sufficiently high to retard solidification), then secondly, injecting the melt through these opposing gates, then thirdly, rapidly cooling to solidification (by circulating heat transfer fluids of much lower temperature, supplied from a cold side supply system).
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: September 18, 2001
    Assignee: Galic Maus Ventures LLP
    Inventors: Steven M. Maus, George J. Galic, John R. Filipe
  • Patent number: 6287488
    Abstract: A method and apparatus for injection molding of high quality thermoplastic parts is such that a conventional movable mold half is mounted on a movable platen of the injection molding machine, and a special stationary mold half is mounted on the stationary platen. The stationary mold half includes a stationary plate secured to the stationary platen, with the stationary plate including stationary mold inserts. Each stationary mold insert has a stationary mold insert surface. An A-half parting line plate is movably attached to the stationary plate, with the A-half parting line plate being movable with respect to the stationary plate and the stationary mold inserts. A driving device, such as a hydraulic cylinder, is disposed between the stationary plate and the A-half parting line plate, with the driving device driving the A-half parting line plate toward and away from the stationary plate.
    Type: Grant
    Filed: February 2, 1999
    Date of Patent: September 11, 2001
    Inventors: Thomas J. Dougherty, Thomas C. Dougherty
  • Patent number: 6284162
    Abstract: Disclosed are novel molding methods for manufacturing thin thermoplastic lenses and, in particular, minus ophthalmic lenses that have thickness of about 1 mm or less at the thinnest point thereof. The molding methods disclosed provide for lenses which lack any abrasion or polishing artifacts on the surface and also lack any negative fining marks below the nominal surface.
    Type: Grant
    Filed: March 25, 1999
    Date of Patent: September 4, 2001
    Assignee: Sola International, Inc.
    Inventors: Jeffrey M. Kingsbury, Michael J. Tuhtan, Robert H. Juul, Martin P. Rolph
  • Patent number: 6270698
    Abstract: Stress-relieved molded acrylic opthalmic lenses, and injection-coining mold processes for molding stress-relieved plus and minus to high-minus diopter ophthalmic lenses of optically superior acrylic resin, able to pass standardized impact drop tests for use in eyeglass lenses, are described. The injection-coining processes use two-plate and three-plate mold assemblies. The cavity of a two plate runnerless mold is partially filled under partial tonnage, and the movable half of the mold controlled to coin and densify the acrylic resin under secondary or full tonnage, when a velocity-pressure changeover point is reached. In a process which employs a three-plate mold assembly, the lens mold cavities are partially filled under less than total clamp tonnage, with a cavity plate held by hydraulic pressure against movable half of the mold.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: August 7, 2001
    Assignee: American Greetings Corp.
    Inventor: Darrell Pope
  • Publication number: 20010002735
    Abstract: A method of manufacturing a diffusion plate for use in a screen plate of projection TV is disclosed. The diffusion plate having a plurality of quadrangular pyramid protrusions almost over one side thereof is manufactured by means of injection molding process of plastic material. This method uses a first molding die having a first molding die surface, a pre-molding die capable of forming a first volume of molding cavity in matching with the first molding die, and a second molding die capable of forming a second volume of molding cavity smaller than the first volume in matching with the first molding die.
    Type: Application
    Filed: January 12, 2001
    Publication date: June 7, 2001
    Inventors: Kashichi Hirota, Junji Fukuda
  • Patent number: 6234629
    Abstract: A contact lens and a method of manufacturing a contact lens having areas of different thickness, the contact lens being compensated for differential shrinkage during the manufacturing process. The unwanted toricity induced by the differential shrinkage caused by a particular manufacturing process is experimentally determined, both in terms of angular position and power. The lens compensation is achieved by providing an equal and opposite power to the unwanted toricity induced by the manufacturing process.
    Type: Grant
    Filed: December 21, 1998
    Date of Patent: May 22, 2001
    Assignee: JOhnson & Johnson Vision Care, Inc.
    Inventors: Susan Neadle, Timothy Clutterbuck
  • Patent number: 6226135
    Abstract: The bottom surfaces of an entering surface-forming portion 1a for forming a light-entering surface 11a of a reflector type prism 11 and of an emitting surface-forming portion 1b for forming a light-emitting surface 11b of the reflector type prism 11 are formed as concave surfaces in a die 1. Even if shrinkage of the reflector type prism 11 occurs during its formation, the light-entering surface 11a and the light-emitting surface 11b are, at least, not formed as concave surfaces, so that a light beam entering the reflector type prism 11 and a light beam emitted from the reflector type prism 11 are prevented from becoming scattered.
    Type: Grant
    Filed: October 28, 1998
    Date of Patent: May 1, 2001
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Mayumi Masui, Mitsuru Hagimoto