Be not technology of superprecision of spherical and optical spare parts

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1. Summarize 1.

The 1 action that is not spherical and optical spare parts is not spherical and optical spare parts is a kind of very important optical part, commonly usedly paraboloid lens, hyperboloid lens, ellipsoid face lens waits. Be not spherical and optical spare parts to be able to acquire spherical and optical part incomparable become goodly like quality, in optical system can very good a variety of correctional resembling that differ, improvement is become like quality, raise a system to differentiate capability, it can with or be not spherical spare parts a few times to replace many spherical parts, simplify thereby instrument structure, reduce cost and reduce instrument weight effectively. The application that is not spherical and optical spare parts to go up in for military use and civil photoelectricity product is very wide also, if be in,camera lens of canal of photography camera lens and viewfinder, pickup, scorch, film puts movie scene, satellite camera lens of infra-red binoculars, videocorder, kinescope and recording CD numerate head, form code numerates instrument of the fiber-optic connect of head, fiber-optic communication, medical treatment in. 1.

The current situation of the superprecision technology that 2 abroad are not spherical spare parts since 80 time, appeared to make a variety of new blame spherical superprecision technology, basically have: Technology of technology of turning of diamond of dot of sheet of computerized numerical control, grinding of computerized numerical control, computerized numerical control is ionic bundle of figuration technology, computerized numerical control exceeds accurate polish technology and blame spherical duplicate technology, these machine a method, basically solved the problem that all sorts of place in be not spherical lens to machine exist. Before 4 kinds of methods used numerical control technology, all have treatment precision is taller, efficiency is advanced characteristic, comfortable produce at batch. When undertaking spherical spare parts is machined is not, the element such as the data that should consider to machine a spare parts, appearance, precision and caliber, wait for weak qualitative data to copper, aluminium, can nod diamond cutting with sheet (the method of SPDT) undertakes superfinishing, to glass or plastic wait, basically use currently first superprecision its mould, after that production of reoccupy figuration law is not spherical spare parts, to other the brittleness material of a few tall hardness, basically be through exceeding nicety grinding is mixed at present exceed the method such as accurate and abrade, polish to undertake machining, additional. Still have the non-traditional machining that is not spherical spare parts if the technology is ionic bundle of polish. Personal general surpasses a lot of foreign companies accurate turning, grinding, abrade and polishing treatment collect makes an organic whole, and develop nicety of favorable balance of trade compound treatment system, one 100A(H) of the AHN60 ― 3D of the Nanocentre that the Nanoform300 that produces like Rank Pneumo company, Nanoform250, CUPE develops, Japan, ULP has compound treatment function, the treatment that can be not spherical spare parts so is more quick. 1.

3 our country are not the current situation our country of technology of superprecision of spherical spare parts to begin the research of superprecision technology from the ability at the beginning of 80 time, lagged behind 20 years full than abroad. In recent years, this job begins better unit to have nicety of aviation of institute of Beijing machine tool, China place of smooth machine of Changchun of mechanical institute, Harbin Institute of Technology, Chinese Academy of Sciences applies optical key laboratory to wait. For the better research that develops pair of this superprecision technologies, national defence division is versed in appoint at was in China 1995 institute of aviation nicety machinery built the key laboratory that home is engaged in superprecision technology the first times considering above all. 2. Be not spherical spare parts to exceeded company of Unio Carbide of United States of accurate cutting processing technique to succeed at was being developed 1972 the blame of means of R ― θ is spherical achieve treatment machine tool. This is a lathe of double coordinate numerical control that has positional feedback, can change the corner θ of blade holder slideway and radius R in real time, implementation is not spherical lens face treatment. Treatment diameter amounts to φ 380mm, the appearance precision that processes work is ± 0.

63 μ M, exterior surface roughness is Ra0.

025 μ M. Rub Er company uses 18AG of ― of M of 3 coordinate pilot to be not spherical treatment machine tool at was being developed above all 1980, this kind of machine tool can machine the metallic illuminator with all sorts of spherical blame of diametical 356mm. Company of British Rank Pneumo uses laser feedback pilot at was being rolled out to the market 1980 two axes linkage machines a machine tool (MSG ― 325) , the blame that this machine tool can machine a diameter to be 350mm is spherical metallic illuminator, precision of treatment workpiece appearance is amounted to 0.

25-0.

5 μ M, ra is in exterior surface roughness 0.

01-0.

Between 025 μ M. Rolled out the machine tool such as ASG2500, ASG2500T, Nanoform300 again subsequently, this company is on the foundation of afore-mentioned machine tools, give out Nanoform600 at leaving 1990, the blame that this machine tool can machine a diameter to be 600mm is spherical illuminator, the appearance precision excel that processes work 0. 1 μ M, excel of exterior surface roughness 0.

01 μ M. The delegate is current of a Gao Shuiping exceeding accurate diamond lathe is American Lawrence. Lifumoer (LLNL) lab developed successful LODTM 1984, it can machine a diameter to amount to 2100mm, its treatment precision can amount to the workpiece that hefts 4500kg 0.

25 μ M, ra0 of exterior surface roughness.

0076 μ M, this machine tool can be machined planar, spherical reach blame is spherical, the part that basically is used at machining place of project of laser nuclear fusion to need, part that infrared device uses and illuminator of large celestial body. Institute of project of nicety of British Cranfield university (what CUPE) develops is large exceed machine tool of cutting of face of right lens of accurate King Kong, the blame that can machine binoculars of celestial bodies of large X ray to use is spherical illuminator (the biggest diameter can amount to 1400mm, the biggest length is the conic lens) of 600mm. It is OK that this institute returned development to succeed treatment is used at X ray binoculars inside circumgyrate paraboloid and outside the diamond cutting machine tool of illuminator of side circumgyrate hyperboloid. The superprecision machine tool that Japan develops basically is the lens that is used at machining civil product place to need and illuminator, the treatment machine tool that at present Japan makes has: The ULG ― L00A(H) that Toshiba machinery develops not × of the AHN10 of machine of work of field of the 2 ASP ― L15 that jump over a company, abundant, AHN30 25, machine tool of spherical treatment of blame of AHN60 ― 3D. 3. Be not spherical spare parts to exceed accurate grinding processing technique 3.

1 blame is spherical the spare parts exceeded company of Rank Pneumo of England of device of grinding of essence of life to was developed 1988 improve model machine tool of ASG2500, ASG2500T, Nanoform300, these machine tools can receive cutting treatment not only, and also can undertake grinding with diamond emery wheel, the blame that can machine a diameter to be 300mm is spherical metallic illuminator, the appearance precision that processes work is 0.

3-0.

16 μ M, exterior surface roughness amounts to Ra0.

01 μ M. Roll out Nanoform250 superprecision system again recently, this system is a two axes exceed accurate CNC machine tool, can undertake on this machine tool turning can undertake exceeding raise close grinding again exceeding nicety already. Still can undertake exceeding accurate polish. The most outstanding characteristic is OK the part of optics of hard fragile data that direct grinding gives what can achieve optical system to ask to have knead dough of optical surface quality precision. This machine tool used a lot of advanced Nanoform600, Optoform50 to devise an idea, diameter of workpiece of the biggest treatment amounts to the machine tool 250mm, it lifts through device makes the diameter of workpiece of the biggest treatment of the machine tool achieves 450mm, pass the liquid that controls perpendicular direction additionally static press slideway (Y axis) still can spare parts of grinding blame axial symmetry, the resolution of system of machine tool numerical control is amounted to 0.

001 μ M, positional feedback component adopted resolution for 8.

The grating of 6nm or resolution are 1.

The laser interferometer of 25nm, the face that processes work precision is amounted to 0.

25 μ M, ra0 of excel of exterior surface roughness.

01 μ M. NextpageNanocentre250, Nanocentre600 is a kind of 3 axes exceed accurate CNC to be not device of spherical Fan Cheng, it can satisfy only place and ductility grinding the use requirement of two respects, design through structure of rationalize machine tool, use system of drive of tall stiffness servo and liquid static press bearing to make the machine tool has taller closed circuit stiffness, the resolution of X and Z axis is 1.

25nm, this machine tool is considered as to accord with modern technology standard. The Nanocentre that CUPE produces is not spherical and optical spare parts to machine a machine tool, treatment diameter amounts to 600mm. Face precision excel 0.

1 μ M, ra0 of excel of exterior surface roughness.

01 μ M. CUPE still is research of American Kodak company, design and production the biggest on current world exceed grinding machine of spare parts of optics of accurate and large CNC " 0AGM2500 " , this machine tool basically is used at the treatment of the hard fragile data such as optical glass, can be machined and measure 2.

5m × 2.

5m × 0.

The workpiece of 61m, what it can machine square giving 2m is asymmetrical optical lens face, the appearance error of lens face is 1 μ M only. The AHN60 ― 3D that machine of work of Japanese abundant field develops is a CNC grinding of three-dimensional cut form and turning machine tool, the optical part that it can play figure of grinding and turning axial semmetry in X, Y and Z3 axle control, can mix in X, Y the grinding below 2 half axle control and turning are not Z axis spare parts of axial symmetry optics, the cut form precision that processes work is 0.

35unl, exterior surface roughness amounts to Ra0.

016 μ M. The ULG ― 100A(H) that additionally Toshiba machinery develops exceeds unit of accurate and compound treatment, it uses the method that controls two axes respectively, realized the cutting of mould of spherical to be not lens and grinding, the journey of its X axis and Z axis is 150mm and 100mm respectively, positional feedback component is resolution for 0.

The grating of 01 μ M. 3.

2 blame are spherical and optical the learned man of Japan of technology of ELID mirror grinding of the spare parts is old dark whole wait for a person from 1987 emery wheel of hard to exceeding abrasive undertook study, developed use electroanalysis the filing of In Process Dressing(ELID) , realized the grinding of mirror grinding of high to hard fragile data grade and ductility means, now this method the application with successful oneself at the spherical, superprecision that is not spherical lens, mould. System of grinding of ELID of principle of ① ELID mirror grinding includes: Metallic bond exceeds imperceptible granuality to exceed hard abrasive emery wheel, electroanalysis nap power source, electroanalysis nap electrode, electrolyte (hold grinding fluid concurrently) , the brush that receive report and machine tool equipment. In grinding process, emery wheel connects through receiving the anode of electric brush and power source, the negative pole that installs the nap electrode on the machine tool and power source is conterminous, between emery wheel and electrode pouring electrolyte, such, the electrolyte between emery wheel and power source, emery wheel, electrode, electrode forms a whole electrochemistry system. When using ELID grinding, the emery wheel that uses to place, power source, electrolyte all has a few special demands. The hydrate that asks the bond of emery wheel has element of good conductivity and electrolyte, bond or oxide are not electric, and not dissolve at water, the power source that ELID grinding uses, the direct current source that can use electrochemical machining or the pulse power source that use all sorts of weaveform or dc base quantity pulse power source. In ELID grinding process, electrolyte is divided outside regarding grinding as fluid, still rising to reduce grinding area temperature and decrease rub the action of hold up, ELID grinding uses water-solubility grinding liquid commonly, belong to completely base the mechanical intensity of bond emery wheel is high, measure through set electroanalysises suitably, emery wheel wears away small. Can get tall appearance precision at the same time. Apply this principle, can come true to arrive from plane blame is spherical, of the optical component of all sorts of appearance exceed accurate mirror grinding. System of test of ② ELID mirror grinding is on the machine tool of ASG ― 2500T of Rank Pneumo company, mount wait for composition by fluid of emery wheel, power source, electrode, grinding greatly dark 1000# is used when 400# , semifinishing machining is being used when thick form cutting of semifinished product of whole ELID system or 2000# , 4000#(is used when making mirror grinding average bead diameter is 4 μ M) about or diameter of 8000#(average bead is 2 μ about, electroanalysis the power source that build fighting spirit () of ELID power source, those who use is to sort type of voltage of high frequency pulse continuously special power source, working voltage is 60V, electric current is L0A. Uses grinding liquid, the requirement when using uses pure water to mix M of ― of AFH of water-solubility grinding fluid CEM is 50 times more attenuant. Method of experiment of ③ ELID mirror grinding and experimental result are made when be not spherical treatment, the bowl form emery wheel that goes up in workpiece axis through installation (emery wheel of diamond of 325# cast-iron bond is φ a figuration system that 30 × W2mm) has making the same score emery wheel is whole, make 10min electroanalysis after earlier Xiu Rui, through the semifinishing machining of the kibble of 400# and 1000# , final reoccupy 4000# undertakes ELID mirror grinding, in exceed nicety to be not spherical treatment machine tool to go up, technology of grinding of ELID of have the aid of, successfully treatment gave 7 blame of ― of optical glass BK spherical lens. Face precision achieves excel 0.

2 μ M, exterior surface roughness amounts to Ra20nm, and to a bit soft the blame that waits for material like LASFN30 and Ge is spherical treatment, can achieve face precision excel likewise 0.

2-0.

3 μ M, exterior surface roughness amounts to Ra30nm. 4. Be not spherical spare parts exceed accurate polish (abrade) the technology exceeds accurate polish is the method of a kind of treatment with treatment extremely slow rate. Do not suit appearance model to be machined into the law, in recent years, the flying development that because shortwave grows instrument of optical component, OA and AV machine,waits, raised taller requirement to the exterior surface roughness of the spare parts, return better without more accurate than exceeding polish practical method so far, ask when the exterior surface roughness of the spare parts especially excel 0.

When 0l μ M, this kind of method is indispensable, very expensive to appearance precision requirement work, when if use,undertaking grinding, its appearance precision will be taken the effect that gives fixed position precision directly by the machine tool, achieve place reaction, the treatment effect that causes from this, in workpiece apparently presence is likewise little sunken part, be in usually, can obtain ripple to rise and fall only bigger surface. Japanese Osaka university is versed in the person such as Sen Yong learning a ministry Professor Zhi used EEM to develop a kind of 3 axes (Fan Cheng device of optical surface of numerical control of X, Z, C) , when using this device to machine, be in at the same time workpiece apparently control gets together the detention time of amine fat ball, use at the same time get together the content whole field of object of treatment of scanning of amine fat ball, use this device to be able to machine the aleatoric curved surface of high accuracy. 5. The machining method such as the cutting that the technology of CVM(Chemical Vaporization Machining) that is not plasma of spherical spare parts uses extensively at present, abrade, polish, because process the account such as the limitation of character and morals that is put in tiny flaw or crystallization in material, no matter how raise treatment precision, improve treatment plant, always put in certain limitation, for this, japanese Osaka university is versed in Sen Yong learning a ministry is teaching the new treatment technique that offerred treatment of gas of a kind of chemically, call plasma CVM way, this is one kind uses atomic chemistry to react, acquire a kind of technology that exceeds narrow face, its machine principle and plasma quarter corrode is same, in plasma, the dissociate that is activationed base react at rising formerly with workpiece surface, will become volatile member, evaporate through gas realize treatment, the plasma of a generation falls in high-pressured force, can generate the dissociate with very high density base, so method of this kind of treatment can achieve the treatment rate with compare of machining method photograph. Below high-pressured force, because the average and free travel of aeriform element is dinky, plasma confine is near electrode. Can pass electrode scanning so, treatment goes out 0.

The spare parts of the aleatoric appearance of precision of 01 μ M, can machine monocrystalline silicon plane with the speed of 50 μ M/min additionally, the exterior surface roughness that processes work can be amounted to 0.

1nm(Rrms) . Leave a century, the blame that in silicon chip treatment and semiconductor exposure device use is spherical in a lot of domains such as lenticular treatment, applied CVM technology, current somebody is considering to pass the combination of CVM and EEM, the aleatoric curved surface of the atomic class evenness such as the X ray illuminator that treatment synchrotron uses. 6. Be not spherical spare parts the polish that duplicate technology uses control eliminate ply (abrade) the blame that the method can make a high accuracy is spherical spare parts, but with general optical spare parts treatment method photograph is compared, the treatment efficiency of this kind of method is very low, one of methods that solve this problem have duplicate technology, namely the technology of mould pressing figuration of plastic inject figuration and glass, this kind of technology can make one part be not spherical lens. Figuration of plastic lens inject is will fused colophony infuse mould inside, use force at the same time, cool at the same time the treatment method of solidify, this kind of method can undertake cheap, big batch is produced, but the certain issue that is put in plastic oneself, if temperature change, moisture absorption causes the change of lenticular refractive index. Mould pressing figuration of glass is the first-rate that replaces lens of cutting, grinding, abrade treatment, prism old mass production method of small-sized spare parts. Technology of mould pressing figuration is the mould the temperature inside controls the glass in punch to transfer temperature of bate of temperature above P the following, inside the mould, enter the glass that has liquidity, pressurization figuration, and maintain above of 20s of this kind of condition, till figuration vitreous temperature distributings to be changed equably, make the appearance precision of the mould 0.

1 μ M, exterior surface roughness is made 0.

01 μ M is the following, pressurization figuration falls in afore-mentioned conditions, can machine a spare parts with mould precision close. CNC Milling CNC Machining