Arnold International
Image forming lens
 An image-forming lens made of five lens elements having refractive power, from the object side, of negative, negative, positive, positive, and negative. The distance between the image side of the surfaces of second and third lens elements is made greater than or equal to 3.4 f, and less than or equal to 7.5 f, where f is the focal length of the image-forming lens, so as to minimize spherical aberration, coma, and astigmatism. The image-forming lens thus formed is a retro-focus lens having a half-picture angle of about 80.degree. and an F# of about 1.8. 
Fuji Photo Optical Co., Ltd.
G
G02B
inventional
Akiko Hiroshi
Nagahara Yamada