摘要(英) |
Lens manufacturing assembly tolerance is a necessary issue for every lens optical factory, but its processing cost and optical imaging quality vary greatly from one optical factory to another with different technologies. This paper is analysis of glass lens material characteristics and lens manufacturing and lens assembly tolerances on its lens imaging quality.
This paper first analyzes the relationship between refractive index and wavelength of glass lenses, the chemical properties of glass and the relative price, and the price of the material should be considered when designing, so that a cheap lens with good imaging quality can be designed, because aspheric glass lenses will be used, so glass materials with a Tg value less than 550C should be used.
Because the design should not only consider the room temperature environment, but also consider the effect of temperature change, and analyze the relationship between the refractive index of glass and temperature changes. The temperature change and thermal expansion coefficient will affect the lens parameters. Different lens materials have different thermal expansion coefficients. After the temperature changes, the lens parameters will change, such as the radius of curvature, lens thickness, air gap and aspheric coefficient. The relationship between the optical power of the lens and the temperature, the refractive index of the lens can be compensated by the thermal expansion coefficient of the lens barrel material or the thermal expansion coefficient of different lens materials, and finally achieve the purpose of heat dissipation.
Optical distortion in the half-view angle θ approximation 90, tan90=, then the paraxial image height is infinite, but the real image height can not be infinite, if the lens optimization design process, optical distortion or the ideal image height as the target value, then the real image height in the half-view angle between 75 and 90, the real image height can not increase sharply, so the real image height will become a certain value, the image will overlap together. In order to change this situation, the definition of ideal image height needs to be changed, so that the ideal image height becomes a linear change, so in the design of large angle or wide-angle lens design, in order to avoid this shortcoming to use F-theta distortion to determine the degree of distortion of the imaging surface. And the human eye is sensitive to changes in light, the human eye will notice the difference between the brightness of the center of the picture and the edge, so the design should consider the relative illumination.
There will be tolerances during manufacturing and assembly, and tolerances will degrade the imaging quality of the designed optical system. Components with smaller tolerances mean more difficult manufacturing and higher prices, increasing cost pressure and manufacturing difficulty. Therefore, in the tolerance setting of the components, the tolerance range should be enlarged without sacrificing too much lens quality. This will not only reduce the cost, but also make it easier to manufacture. Finally, analyze the tolerance analysis in CODE V to calculate the cumulative probability function distribution of the lens manufacturing yield. The probability used by CODE V is the probability distribution of 2σ, which means that the system manufactured with a 97.7% probability will have this performance.
Finally, apply these theories to the design of the scanner lens, the optical path design of the Blu-ray optical read-write head, the design of the 2 million pixels mobile phone lens, and the design of the wide-angle lens of the monitor. The design must achieve its own design goals.
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參考文獻 |
參考文獻
[1] T. H. Jamieson, “Thermal effects in optical systems,” Opt. Eng. 20, 156-160 (1981).
[2] M. H. Horman, “Temperature analysis from multispectral infrared data,” Appl. Opt. 15(9), 2099–2104 (1976).
[3] M. J. Duggin, “Discrimination of targets from background of similar temperature, using two-channel data in the 3.5-4.1-um and 11–12-umregions,” Appl. Opt. 25(7), 1186–1195 (1986).
[4] Y. Tamagawa and T. Tajime, “Dual-band optical systems with a projective athermal chart: design,” Appl. Opt. 36(1), 297–301 (1997).
[5] I. Friedman, “Thermo-optical analysis of two long-focal length aerial reconnaissance lenses,” Opt. Eng. 20, 161-165 (1981). [6] W. Shi and M. E. Couture, “Long wave infrared zoom projector thermal analysis and compensation,” Opt. Eng. 39, 2708-2714 (2000).
[7] M. Bayar and Ő. F. Farsakoğlu, “Mechanically active athermalization of a forward looking infrared system,” Infrared Physics & Technology 43, 91-99 (2002).
[8] C. W. Kuo, C. L. Lin, and C. Y. Han, “Dual field-of-view midwave infrared optical design and athermalization analysis,” Appl. Opt. 49(19), 3691–3700 (2010).
[9] C. W. Kuo, “Achromatic triplet and athermalized lens assembly for both midwave and longwave infrared spectra,” Opt. Eng. 53, 021102 (2014).
[10] Y. Tamagawa, S. Wakabayashi, T. Tajime, and T. Hashimoto, “Multilens system design with an athermal chart,” Appl. Opt. 33, 8009-8013 (1994).
[11] Y. Tamagawa, T. Tajime, “Expansion of an athermal chart into a multilens system with thick lenses spaced apart,” Opt. Eng. 35, 3001-3006 (1996).
[12] Schott optical glass collection data sheets English 2022.
[13] Schott optical glass overview excel table English January 2022.
[14] Schott optical glass pocket catalog row.
[15] Schott optical components production capabilities May 2013 eng.
[16] Schott abbe diagram nd-vd jam.
[17] Schott, “TIE-29: Refractive index and dispersion,” in Proc. Schott Technical information U.S. (February 2016).
[18] Schott, “TIE-19: Temperature coefficient of the refractive index,” in Proc. Schott Technical information (July 2016).
[19]高鳳遙: 超大廣角鏡頭在溫度-20C至60C對熱的分析與校正之鏡頭設計,國立中央大學光電科學研究所碩士論文,中華民國一百零五年。
[20] Y. Bai, T. W. Xing, W. M. Lin and W. M. Xie, “Athermalization of middle infrared optical system,” J. Appl. Opt. 33(1),181-185 (2012).
[21]徐英舜: 汽車超大廣角於溫度-30C至70C消熱差與高相對照度之鏡頭設計,國立中央大學光電科學研究所碩士論文,中華民國一百零六年。
[22]黃前銘: 四百萬畫素DLP大口徑投影機鏡頭設計與溫度、電視畸變、橫向色差、相對照度之探討,國立中央大學光電科學研究所碩士論文,中華民國一百零七年。
[23] W. S. Sun, C. M. Huang, and J. S. Lin, “Discussion of temperature, TV distortion, and lateral color of a 4-megapixel DLP projector lens,” OSA Continuum 2 (11), 3188-3203 (2019).
[24] Y. J. Kim, Y. S. Kim and S. C. Park, “Simple graphical selection of optical materials for an athermal and achromatic design using equivalent Abbe number and thermal glass constant,” Journal of the optical society of Korea 19, 182-187 (2015).
[25]維基百科-畸變(https://zh.wikipedia.org/wiki/%E7%95%B8%E8%AE%8A)
[26] S. Thibault, J. Gauvin, M. Doucet and M. Wang, “Enhanced optical design by distortion control,” Proc. SPIE 5962, 596211 (2005).
[27] 周柏亨,「大口徑投影機鏡頭設計投射在螢幕上之直線鑑別率、橫向色差鑑別率、相對照度與MTF並對溫度變化作分析」,中央大學,碩士論文,民國109年。
[28] CODE V “Tolerancing Reference Manual” Version 2022.03 March 2022.
[29]楊家逢: 模組化光學讀寫頭的設計與光學讀寫頭應用在角度量測的研究,國立中央大學光電科學研究所碩士論文,中華民國九十六年。
[30] Daniel Malacara, Optical Shop Testing, 2nd ed. (Wiley, 1992).
[31] Schott tie-04 test report for delivery lots of optical glass eng.
[32] H. Lowenthal, “PHOTOGRAPHIC OBJECTIVE OF THE TRIPLET TYPE” U.S. patent 2,645,157 (Jan. 5, 2010).
[33] Toshiba, “T4K71” in image sensor, https://toshiba.semicon-storage.com/tw/top.html
[34] Omni Vision, “OV5695” 5-megapixel product brief.
[35] M. Horimoto, “Fish eye lens system” U.S. patent 4,412,726A.
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