Unity-magnification copying lens having resolution power of refraction limit

Abstract

Abstract PURPOSE: To obtain resolution power of a refraction limit with aberration being compensated extremely minutely, by satisfying the specified condition by the use of 14 groups of 18 lenses with the refraction planes being arranged so that a focus forms a symmetricale plane. CONSTITUTION: An optical system is formed by the use of 14 groups of 18 lenses, which are divided into 7-front groups of 9 lenses and 7-rear groups of 9 lenses, with the refraction planes being arranged so that a focus 100 forms a symmetrical plane. In the case where the focus distance of the entire system is 171.0835, a numerical aperture is 0.164, and the image hight is 25; and where r is curvature radius of the refraction planes, d is the distance between the refraction planes, N is the refraction rate of the glass spectrum g, and υ is Abbe's number, the dimensions of the lenses are specified as shown in the Table in the Figure. This configuration results in unitylens magnification, and near zero values of a spherical aberration factor, a coma factor, an astigmatism factor, and distortion aberration factor, and of Petzval's factor. Then, a unity-magnification lens having resolution power of a refraction limit, that is an excellent copy lens for non-contact printing in manufacturing ICs can be obtained. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Koichi Kobayashi

Bibliographic Details