The effect of change in normative approach on the evaluation of surface scratches on high-precision optical surfaces

Plastic optical components and lenses produced in mass quantities are usually manufactured using high-precision plastic injection technology. For that, high-precision plastic moulds with aluminium optical inserts made with extremely high dimension accuracy and high optical surface quality are used. Ultra-high precision single-point diamond turning have been successfully used in shaping optical mould inserts from various aluminium grades such as traditional 6061. However, extreme care should be taking when selecting machining parameters in order to produce optically valid surfaces before premature tool wear takes place especially when the machined optical materials has inadequate machining database. The current experimental study looks at the effect of cutting conditions on optical surfaces made from aluminium. The study embarks on helping establish some diamond machining database that helps engineers select the most favourable cutting parameters. The papers reports on the accuracy and surface finish quality received on an optical surface made on mould inserts from a newly developed aluminium alloy. Rapidly solidified aluminium (RSA) grades have been developed recently to address the various problems encountered when being cut by single-point diamond turning operation. The material is characterised by its extremely fine grained microstructure which helps extend the tool life and produce optical surfaces with nanometric surface finish. It is found the RSA grades can be successfully used to replace traditional optical aluminium grades when making optical surfaces. Surface finishes of as low as 10 nanometres and form accuracy of less than one micron can be achieved on RSA.

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Automatized Control of Polymer Optical Parts

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.743.459 ◽

2017 ◽

Vol 743 ◽

pp. 459-462

Author(s):

Fedor Glushchenko ◽

Timur Grishukov ◽

Sergey Vasilkov

Keyword(s):

Optical Properties ◽

Injection Molding ◽

High Precision ◽

Industry 4.0 ◽

Control Method ◽

Optical Surfaces ◽

High Effect ◽

Complicated Process ◽

The Creation

The manufacturing of polymer optical parts is a technologically complicated process because of a high precision of optical surfaces. Every responsible part has to be checked for homogeneity due to its high effect on optical properties. Thus, the creation of an area for automatized part control after injection molding is a pertinent goal. The study has applied the concept “Industry 4.0” to create a model of automatized area for polymer lens control. A photoelasticity control method for photosensitive materials was chosen.

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Research on the Online Test Principle and Error Analysis of Aspherical Optical Surfaces

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.552.434 ◽

2013 ◽

Vol 552 ◽

pp. 434-439

Author(s):

Da Mu ◽

Quan Yong Li ◽

Bo Qi Wu ◽

Yu Nan Du

Keyword(s):

High Precision ◽

Precision Measurement ◽

Measurement Errors ◽

Surface Shape ◽

High Precision Measurement ◽

Aspherical Surface ◽

Optical Surfaces ◽

Advantages And Disadvantages ◽

Swing Arm ◽

Key Factor

For tFor t For tFor the imaging advantages of aspheric optical component, it has been widely used in the aviation, aerospace, defense and civilian high-technology. Aspherical surface shape test is a key factor restricted aspheric processing and a complex sophisticated testing techniques. The well known measurement methods are faulty. Each method has advantages and disadvantages; many methods cannot be used for online testing. In this paper，the geometric principle of a swing-arm profilometer as a novel method to measure aspherics is introduced．The deviation between the actual and the ideal of aspherical surface shape is confirmed by the high-precision measurement for the vertical height with a specific path on the aspherical optical surfaces. By adjusting the location of measuring devices to maintain the distance of rotation center to the center of workpiece equal to the length of swing-arm,we can achieve the measurement for the workpiece of different machining tool. The measurement system mainly consists of the lifting and landing system of the high-precision axis,the high-precision level turntable rotary table, the high rigidity measuring arm and the high precision measurement sensors. And the follow-up data processing puts forward a number of error correction models at the same time. The advantages of the measurement method are that the measurement sports is only a simple turning motion .It will be helpful to reduce measurement errors and improve the efficiency of measurement.

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