- Email: [email protected]
Diamond Optics III
strict requirements on the metrology instrumentation used to guide the fabrication process; in general, the accuracy of the measurements must be an order of magnitude better than the quality of the finished product. This is true for each of the measured parameters, which include axial figure, circumferential figure, inner diameter, and surface microroughness. Axial figure, circumferential figure, and inner diameter data are used to form maps of the inside surface of the optics, and form the basis for the subsequent fabrication cycle. Surface microroughness is used to determine the scattering performance of the system. This paper describes the facility used for the measurement of circumferential figure and inner diameter. 3 Refs. Index Terms: Telescopes - space applications: Astrophysics - instruments; Optical instruments: X-rays; Astronomy - instruments; AXAF optics. 8, R. V. Peterson, C. W. Bowers. "Contamination removal by CO2 jet spray," Optical System Contamination: Effects, Measurement, Control II, Vol 1329, pp. 72-85. Int Soc for Optical Engineering, Bellingham, WA. Space optics have very stringent off-axis rejection requirements. As a consequence scatter from contamination must be maintained at very low levels during the life of the optics. Studies on the effectiveness of the jet flush in removing particle fallout and Arizona standard fine dust on polished optical substrates have been carried out at ambient pressure and vacuum. These studies have shown that the CO 2 jet flush is a viable method for removing contaminants from optical surfaces with no damage to the surface. The studies also show that the jet flush has potential for use as an on-orbit cleaning device for space optics. 4 Refs. Index Terms: Optical instruments - space applications; Optical systems - decontamination; Flow of fluids - jets: Carbon dioxide: Contamination removal; Jet sprays: Surface cleaning.
9, L. Darnton, S. Silott, D. Willis, "Correlation of BRDF and profilometry for sub-Angstrom surfaces," Stray Radiation in Optical Systems, Vol 1331, pp. 286-292. lnt Soc for Optical Engineering, Bellingham, WA. Recent improvements in optical polishing techniques have made possible optical surfaces exhibiting random microroughness levels of less than one Angstrom rms. One such mirror, recently produced by the Photronics Corporation and tested at TRW. exhibited a measured microroughness of 0.22 A r m s but had scatter behavior which was not commensurate with this value. The problem was discovered to be point defects in the surface which were not detected during profilometry, and which would not have been problematic in mirrors having microroughnesses of a few ,~ rms. It is concluded that visual scatter inspection, at a minimum, should be used as an in-process polishing diagnostic, in addition to profilometry. 4 Refs. Index Terms: Mirrors - optical properties; Light - scattering; Surfaces roughness measurement; Polishing - quality control; Sub-angstrom surface microroughness; Optical surface quality control; Surface profilometry; Bidirectional reflectance distribution function. 10, S. C. F. Sheng, O. Berendsohn, M. R. Schreibman, L. M. Cohen, "Correlation of RTV properties to test data and its effect on the AXAF mirror performance," Advanced Optical Manufacturing and Testing, Vol 1333, pp. 314-324. lnt Soc for Optical Engineering, Bellingham, WA. Using RTV rubber as an interface between mirror elements and their supporting structures during grinding and polishing was proposed for the Advanced X-Ray Astrophysics Facility (AXAF) for glass safety concerns. This paper shows that the mirror performance is quite sensitive to the compression modulus of GE RTV-60 which, like all other rubberlike materials, is very difficult to characterize by testing and even more difficult to characterize analytically. Consequently, using representative RTV properties in mirror analyses only produces nominal performance predictions. The envelope of the range of performance has to be determined by using both extremes of the RTV compression modulus. This paper also presents a comparison between compression moduli generated via testing and that from semi-empirical formulas. 2 Refs. Index Terms: Mirrors performance: Astrophysics: Rubber; Grinding: AXAF mirrors. 11, A. Ishibashi, S. Tanaka, S. Ezoe, "Design and manufacture of a CNC gear grinder capable of mirrorlike finishing," JSME International Journal, Series I11 (Vibration, Control Engineering, Engineering for Industry), 33(2), pp. 245-50. (June 1990). In order to efficiently obtain mirrorlike ground gears, the authors designed and made a computer numerically controlled (CNC) gear grinder. For obtaining the desired surface finish, a cubic boron nitride grinding wheel with a medium grain size was used under creep-feed grinding conditions with grinding fluid. The profiles of the gear being ground were generated by a rolling motion produced by a master worm gear and a high-accuracy ball screw. The trial gear grinder could produce spur gears with mirror-like tooth surfaces having a roughness of about 0.2 lure Rma x By controlling the two servomotors, gears with any type of tooth profile modification could be ground easily. Using the same principle, an intermittent grinding process was introduced for preventing grinding burn under severe grinding, and ground gears with modules of two and three were made without a cutting process. Index Terms: Computerized numerical control; Grinding; Machine tools; Surface topography; Surface roughness; CNC gear grinder; Mirrorlike finishing; Mirrorlike ground gears; Computer numerically controlled; Gear grinder; Surface finish; Cubic boron nitride grinding wheel; Medium grain size; Creep-feed grinding conditions; Grinding fluid; Master worm gear; High-accuracy ball screw; Spur gears: Mirror-like tooth surfaces; Servomotor; Tooth profile; Intermittent grinding process; Grinding burn. 12, M. Yoshikawa,
"Development and performance of a diamond film polishing apparatus
with hot metals,"
Diamond Opties 111, Vol 1325, pp. 210-221. lnt Soc for Optical Engineering, Bellingham, WA. The diamond film polishing apparatus with hot metals has been presented. Diamond films deposited by both microwave plasma CVD and arc discharge plasma jet CVD are used as workpieces. As a diamond film sways on a polishing plate made of an iron or a nickel heated to 750=950 °C, it is finished to fiat and glass-like surfaces without any exfoliation. Not only swaying speed but also polishing pressure in this apparatus are extremely low in comparison to a conventional mechanical polishing method. When a cast iron and a molybdenum are used as a polishing plate, polishing is not advanced. The polishing rate is highest in a vacuum atmosphere. Among gas atmospheres, the rate is highest in a hydrogen atmosphere. These result show that a diamond film is polished by the diffusion of carbon into a polishing plate. When a diamond film surface is too rough to polish by this apparatus, the surface planing with YAG laser is applied, then polishing is conducted on the planed surface. 2 Refs. Index Terms: Diamonds - chemical vapor deposition; Films - polishing; Polishing machines - performance; CVD films; Polishing apparatus; MPCVD films; Optimum operating conditions. 13, Anon, A. Feldman, S. Holly, "Diamond Optics I I I , " Vol 1325, 357 pages, lnt Soc for Optical Engineering, Bellingham, WA. This proceedings of the meeting contains 34 papers. The meeting focuses on several aspects of diamond research: deposition, characterization, applications, mechanical, optical and other properties, spectroscopy and polishing. Papers on deposition and
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characterization of diamond-like carbon coatings were also presented. Optically active defects in CVD diamond have been identified and characterized. Features in the Raman Spectrum such as the line width, the relative size of the diamond and diamond-like carbon peak, and the size of the photoluminescence background have been correlated with each other and with the intensity of cathodluminescence features. Index Terms: Diamonds - synthetic; Films - chemical vapor deposition; Optical properties; Polishing; Optical materials - films; Raman scattering; Diamond deposition; DLC films; Optical characterization; Diamond growth. 14, M. Stern, K. Rauber, "Digital position controller for linear axes. 1," Elektronik, 40(3), pp. 54-9. (5 Feb. 1991). Describes the hardware and controller structure of the Compax position controller designed for a wide variety of machine too! applications. The general features and advantages of digital control are outlined, followed by a consideration of current and position/speed control loops implemented in the system. Details of wordlength, sampling and timing for the various control functions are included. Index Terms: Controllers; digital control; Machine tools; Position control: Linear axes: Controller structure; Compax position controller; Machine tool applications; Digital control; Speed control; Control functions 15, M. Stern, K. Rauber, "Digital position controller for linear axes. II," Elektronik, 40(4), pp. 74-7. (19 Feb. 1991~. For pt.I see ibid., vol.40, no.3, p.54 (1991). This second part deals with a practical positioning application, showing how the Compax controller can be programmed to control a required profile with specified position, speed and acceleration. The example is a simple two-axis automated handling application; flow charts and code for the two-axis control are included. A brief specification of the Compax system is also given. Index Terms: Controllers; Digital control; Machine tools: Position control; Digital position controller; Machine tools; Compax controller; Profile; Two-axis automated handling application: Flow charts. 16, W. J. Wills-Moren, K. Carlisle, P. A. McKeown, P. Shore, "Ductile regime grinding of glass and other brittle materials by the use of ultra-stiff machine tools," Advanced Optical Manufacturing and Testing, Vot 1333, pp. 126135. Int Soc for Optical Engineering, Bellingham, WA. The disadvantages of traditional methods of forming glass and other brittle materials are discussed and relevant research work into alternative methods are reviewed. The recent work of Cranfield Unit for Precision Engineering (CUPE) is described, together with descriptions of equipment currently being used and new equipment specifically designed for ductile regime grinding of optical components with fixed abrasive wheels. 15 Refs. Index Terms: Glass grinding; Grinding wheels; Materials - cutting; Brittle materials. 17, A. Mayer, R. D. Bramlett, R. D. Day, C. J. Evans, R. S. Polvani. "Electrodeposited coatings for diamond t u r n i n g applications," American Society .for Precision Engineering Conference, Tucson, AZ, 15-18 Apr 1991. American Society for Precision Engineering. PO Box 7918, Raleigh, NC 27695-7918. Electrodeposited coatings are attractive for precision machining operations because thick coatings can be economically applied, with good adhesion, to a variety of substrates. Approximately 20 pure metals and a large number of alloys can be deposited from aqueous solutions. Fused salt and organic solvent electrolytes can be used to lengthen the list of metals that can be electrodeposited. However, both the choice of the metallic coating and the control of the plating process are critical for success in precision finishing of electrodeposited coatings. Some preliminary results at the National Institute of Standards and Technology and at the Lawrence Livermore National Laboratory suggest that electrodeposited nickel-phosphorus alloys are excellent coatings for single point diamond turning from the standpoint of material properties and low tool wear. Electrodeposited aluminum and aluminum alloy coatings also merit consideration for precision finishing where weight is an important factor. 10 refs., 6 figs. Index Terms: Aluminum - electrodeposition; Aluminum alloys - electrodeposition; electrodeposited coatings - uses; Nickel alloys - electrodeposition; Phosphorus - electrodeposition; Aqueous solutions: Electrolytes; Erosion; Machining; Metallic glasses; Organic compounds; Surface finishing: Uranium: Wear: Actinides: Alloys: Coatings; Deposition; Dispersions; Electrolysis; Surface coating. 18, L. Fang, Q. D. Zhou, Y. J. Li, "Explanation of the relation between wear and material hardness in three-body abrasion," International Conference on Wear of Materials, Vol 1, pp. 513-520. ASME, New York, NY, In three-body abrasion the relation between wear weight loss and material hardness is more complicated than that in two-body abrasion. In order to explain the relation short-travel three-body, short-travel two-body and long-travel three-body abrasion tests were done in the present paper. The results showed that: (1) in three-body abrasion the cutting wear and plastic deformation wear coexisted; (2) When material hardness changes, the ratio of cutting wear to plastic deformation wear changes, too. Based on the test results, an expression was proposed by which the relation between wear and material hardness in three-body abrasion could be satisfactorily explained. Index Terms: Wear of materials - theory; Materials - hardness; Metals and alloys - wear; Surfaces - wear; Three-body abrasion. 19, Y. Mori, K. Yamauchi, K. Endo, "Extreme precision machining techniques," Journal ~f the Japan Socieo ¢d Precisi~m Engineering, 57(1), pp. 36-42. (Jan. 1991). Ideal machining is to create a surface which has atomic-level flatness and provides no disturbance crystallographicalty, and can be realized by using physical or chemical phenomena which require no excessive energy for the elimination of atomic-level disturbances. As examples of the development of extreme precision machining, the authors describe applications of EEM (elastic emission machining) and CVM (chemical vaporization machining) technologies for the creation of such ideal surfaces, referring to the concepts of EEM and CVM, and the principles of machining. The authors also describe the physical characteristics of a machined surface examined using SPV (surface photo-voltage) spectroscopy, index Terms: Machining: Surface treatment; Vaporization; Surface photo-voltage spectroscopy; Surface treatment; Precision machining techniques;Flamess; Atomic-level disturbances; Development; Elastic emission machining; Chemical vaporization machining.
20, J. S. Taylor, C. J. Evans, "Fabrication overview: Fabrication of a metal-plated mirror, beginning from a performance requirement," American Society for Precision Engineering (ASPE) conference, Tucson, AZ, 15-18 Apr 1991. American Society for Precision Engineering. PO Box 7918, Raleigh, NC 27695-7918. (UCRL-JC-106935). The principal steps in manufacturing a metal-plated mirror are substrate fabrication, plating, and final surface finishing. The intermediate specifications for these operations, as well as the final specification, are developed (ideally) during an iterative planning process that includes the optical designer, the project engineer, a metrologist, and if necessary a coater (for a final thin reflective coating). Each of these
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9, L. Darnton, S. Silott, D. Willis, "Correlation of BRDF and profilometry for sub-Angstrom surfaces," Stray Radiation in Optical Systems, Vol 1331, pp. 286-292. lnt Soc for Optical Engineering, Bellingham, WA. Recent improvements in optical polishing techniques have made possible optical surfaces exhibiting random microroughness levels of less than one Angstrom rms. One such mirror, recently produced by the Photronics Corporation and tested at TRW. exhibited a measured microroughness of 0.22 A r m s but had scatter behavior which was not commensurate with this value. The problem was discovered to be point defects in the surface which were not detected during profilometry, and which would not have been problematic in mirrors having microroughnesses of a few ,~ rms. It is concluded that visual scatter inspection, at a minimum, should be used as an in-process polishing diagnostic, in addition to profilometry. 4 Refs. Index Terms: Mirrors - optical properties; Light - scattering; Surfaces roughness measurement; Polishing - quality control; Sub-angstrom surface microroughness; Optical surface quality control; Surface profilometry; Bidirectional reflectance distribution function. 10, S. C. F. Sheng, O. Berendsohn, M. R. Schreibman, L. M. Cohen, "Correlation of RTV properties to test data and its effect on the AXAF mirror performance," Advanced Optical Manufacturing and Testing, Vol 1333, pp. 314-324. lnt Soc for Optical Engineering, Bellingham, WA. Using RTV rubber as an interface between mirror elements and their supporting structures during grinding and polishing was proposed for the Advanced X-Ray Astrophysics Facility (AXAF) for glass safety concerns. This paper shows that the mirror performance is quite sensitive to the compression modulus of GE RTV-60 which, like all other rubberlike materials, is very difficult to characterize by testing and even more difficult to characterize analytically. Consequently, using representative RTV properties in mirror analyses only produces nominal performance predictions. The envelope of the range of performance has to be determined by using both extremes of the RTV compression modulus. This paper also presents a comparison between compression moduli generated via testing and that from semi-empirical formulas. 2 Refs. Index Terms: Mirrors performance: Astrophysics: Rubber; Grinding: AXAF mirrors. 11, A. Ishibashi, S. Tanaka, S. Ezoe, "Design and manufacture of a CNC gear grinder capable of mirrorlike finishing," JSME International Journal, Series I11 (Vibration, Control Engineering, Engineering for Industry), 33(2), pp. 245-50. (June 1990). In order to efficiently obtain mirrorlike ground gears, the authors designed and made a computer numerically controlled (CNC) gear grinder. For obtaining the desired surface finish, a cubic boron nitride grinding wheel with a medium grain size was used under creep-feed grinding conditions with grinding fluid. The profiles of the gear being ground were generated by a rolling motion produced by a master worm gear and a high-accuracy ball screw. The trial gear grinder could produce spur gears with mirror-like tooth surfaces having a roughness of about 0.2 lure Rma x By controlling the two servomotors, gears with any type of tooth profile modification could be ground easily. Using the same principle, an intermittent grinding process was introduced for preventing grinding burn under severe grinding, and ground gears with modules of two and three were made without a cutting process. Index Terms: Computerized numerical control; Grinding; Machine tools; Surface topography; Surface roughness; CNC gear grinder; Mirrorlike finishing; Mirrorlike ground gears; Computer numerically controlled; Gear grinder; Surface finish; Cubic boron nitride grinding wheel; Medium grain size; Creep-feed grinding conditions; Grinding fluid; Master worm gear; High-accuracy ball screw; Spur gears: Mirror-like tooth surfaces; Servomotor; Tooth profile; Intermittent grinding process; Grinding burn. 12, M. Yoshikawa,
"Development and performance of a diamond film polishing apparatus
with hot metals,"
Diamond Opties 111, Vol 1325, pp. 210-221. lnt Soc for Optical Engineering, Bellingham, WA. The diamond film polishing apparatus with hot metals has been presented. Diamond films deposited by both microwave plasma CVD and arc discharge plasma jet CVD are used as workpieces. As a diamond film sways on a polishing plate made of an iron or a nickel heated to 750=950 °C, it is finished to fiat and glass-like surfaces without any exfoliation. Not only swaying speed but also polishing pressure in this apparatus are extremely low in comparison to a conventional mechanical polishing method. When a cast iron and a molybdenum are used as a polishing plate, polishing is not advanced. The polishing rate is highest in a vacuum atmosphere. Among gas atmospheres, the rate is highest in a hydrogen atmosphere. These result show that a diamond film is polished by the diffusion of carbon into a polishing plate. When a diamond film surface is too rough to polish by this apparatus, the surface planing with YAG laser is applied, then polishing is conducted on the planed surface. 2 Refs. Index Terms: Diamonds - chemical vapor deposition; Films - polishing; Polishing machines - performance; CVD films; Polishing apparatus; MPCVD films; Optimum operating conditions. 13, Anon, A. Feldman, S. Holly, "Diamond Optics I I I , " Vol 1325, 357 pages, lnt Soc for Optical Engineering, Bellingham, WA. This proceedings of the meeting contains 34 papers. The meeting focuses on several aspects of diamond research: deposition, characterization, applications, mechanical, optical and other properties, spectroscopy and polishing. Papers on deposition and
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characterization of diamond-like carbon coatings were also presented. Optically active defects in CVD diamond have been identified and characterized. Features in the Raman Spectrum such as the line width, the relative size of the diamond and diamond-like carbon peak, and the size of the photoluminescence background have been correlated with each other and with the intensity of cathodluminescence features. Index Terms: Diamonds - synthetic; Films - chemical vapor deposition; Optical properties; Polishing; Optical materials - films; Raman scattering; Diamond deposition; DLC films; Optical characterization; Diamond growth. 14, M. Stern, K. Rauber, "Digital position controller for linear axes. 1," Elektronik, 40(3), pp. 54-9. (5 Feb. 1991). Describes the hardware and controller structure of the Compax position controller designed for a wide variety of machine too! applications. The general features and advantages of digital control are outlined, followed by a consideration of current and position/speed control loops implemented in the system. Details of wordlength, sampling and timing for the various control functions are included. Index Terms: Controllers; digital control; Machine tools; Position control: Linear axes: Controller structure; Compax position controller; Machine tool applications; Digital control; Speed control; Control functions 15, M. Stern, K. Rauber, "Digital position controller for linear axes. II," Elektronik, 40(4), pp. 74-7. (19 Feb. 1991~. For pt.I see ibid., vol.40, no.3, p.54 (1991). This second part deals with a practical positioning application, showing how the Compax controller can be programmed to control a required profile with specified position, speed and acceleration. The example is a simple two-axis automated handling application; flow charts and code for the two-axis control are included. A brief specification of the Compax system is also given. Index Terms: Controllers; Digital control; Machine tools: Position control; Digital position controller; Machine tools; Compax controller; Profile; Two-axis automated handling application: Flow charts. 16, W. J. Wills-Moren, K. Carlisle, P. A. McKeown, P. Shore, "Ductile regime grinding of glass and other brittle materials by the use of ultra-stiff machine tools," Advanced Optical Manufacturing and Testing, Vot 1333, pp. 126135. Int Soc for Optical Engineering, Bellingham, WA. The disadvantages of traditional methods of forming glass and other brittle materials are discussed and relevant research work into alternative methods are reviewed. The recent work of Cranfield Unit for Precision Engineering (CUPE) is described, together with descriptions of equipment currently being used and new equipment specifically designed for ductile regime grinding of optical components with fixed abrasive wheels. 15 Refs. Index Terms: Glass grinding; Grinding wheels; Materials - cutting; Brittle materials. 17, A. Mayer, R. D. Bramlett, R. D. Day, C. J. Evans, R. S. Polvani. "Electrodeposited coatings for diamond t u r n i n g applications," American Society .for Precision Engineering Conference, Tucson, AZ, 15-18 Apr 1991. American Society for Precision Engineering. PO Box 7918, Raleigh, NC 27695-7918. Electrodeposited coatings are attractive for precision machining operations because thick coatings can be economically applied, with good adhesion, to a variety of substrates. Approximately 20 pure metals and a large number of alloys can be deposited from aqueous solutions. Fused salt and organic solvent electrolytes can be used to lengthen the list of metals that can be electrodeposited. However, both the choice of the metallic coating and the control of the plating process are critical for success in precision finishing of electrodeposited coatings. Some preliminary results at the National Institute of Standards and Technology and at the Lawrence Livermore National Laboratory suggest that electrodeposited nickel-phosphorus alloys are excellent coatings for single point diamond turning from the standpoint of material properties and low tool wear. Electrodeposited aluminum and aluminum alloy coatings also merit consideration for precision finishing where weight is an important factor. 10 refs., 6 figs. Index Terms: Aluminum - electrodeposition; Aluminum alloys - electrodeposition; electrodeposited coatings - uses; Nickel alloys - electrodeposition; Phosphorus - electrodeposition; Aqueous solutions: Electrolytes; Erosion; Machining; Metallic glasses; Organic compounds; Surface finishing: Uranium: Wear: Actinides: Alloys: Coatings; Deposition; Dispersions; Electrolysis; Surface coating. 18, L. Fang, Q. D. Zhou, Y. J. Li, "Explanation of the relation between wear and material hardness in three-body abrasion," International Conference on Wear of Materials, Vol 1, pp. 513-520. ASME, New York, NY, In three-body abrasion the relation between wear weight loss and material hardness is more complicated than that in two-body abrasion. In order to explain the relation short-travel three-body, short-travel two-body and long-travel three-body abrasion tests were done in the present paper. The results showed that: (1) in three-body abrasion the cutting wear and plastic deformation wear coexisted; (2) When material hardness changes, the ratio of cutting wear to plastic deformation wear changes, too. Based on the test results, an expression was proposed by which the relation between wear and material hardness in three-body abrasion could be satisfactorily explained. Index Terms: Wear of materials - theory; Materials - hardness; Metals and alloys - wear; Surfaces - wear; Three-body abrasion. 19, Y. Mori, K. Yamauchi, K. Endo, "Extreme precision machining techniques," Journal ~f the Japan Socieo ¢d Precisi~m Engineering, 57(1), pp. 36-42. (Jan. 1991). Ideal machining is to create a surface which has atomic-level flatness and provides no disturbance crystallographicalty, and can be realized by using physical or chemical phenomena which require no excessive energy for the elimination of atomic-level disturbances. As examples of the development of extreme precision machining, the authors describe applications of EEM (elastic emission machining) and CVM (chemical vaporization machining) technologies for the creation of such ideal surfaces, referring to the concepts of EEM and CVM, and the principles of machining. The authors also describe the physical characteristics of a machined surface examined using SPV (surface photo-voltage) spectroscopy, index Terms: Machining: Surface treatment; Vaporization; Surface photo-voltage spectroscopy; Surface treatment; Precision machining techniques;Flamess; Atomic-level disturbances; Development; Elastic emission machining; Chemical vaporization machining.
20, J. S. Taylor, C. J. Evans, "Fabrication overview: Fabrication of a metal-plated mirror, beginning from a performance requirement," American Society for Precision Engineering (ASPE) conference, Tucson, AZ, 15-18 Apr 1991. American Society for Precision Engineering. PO Box 7918, Raleigh, NC 27695-7918. (UCRL-JC-106935). The principal steps in manufacturing a metal-plated mirror are substrate fabrication, plating, and final surface finishing. The intermediate specifications for these operations, as well as the final specification, are developed (ideally) during an iterative planning process that includes the optical designer, the project engineer, a metrologist, and if necessary a coater (for a final thin reflective coating). Each of these
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