Patent ID: 6831794
Filing Date: 2004-12-14
Classification: G02B,G03F

Abstract:
Lens with at least one aspheric lens surface, wherein, on describing the aspheric lens surface by means of Zernike polynomials, the following holds for the aspheric lens surface: P&af;(h)=&it;h2R(1+1-h2R2)+K0+K4*Z4+K9*Z9+K10*Z16+&it;K25*Z25+K36*Z36+K49*Z49+K64*Z64withZ4=(2Ã—h2âˆ’1) Z9=(6h4âˆ’6h2+1) Z16=(20h6âˆ’30h4+23h2âˆ’1) Z25=(70h8âˆ’140h6+90h4âˆ’20 h2+1) Z36=(252h10âˆ’630h8+560h6âˆ’210h 4+30 h2âˆ’1) Z49=(924h12âˆ’27.72h 10+h3150h8âˆ’1680h6+h420h4âˆ’42h2+1) Z64=(3432h14âˆ’12012h12+16632h110âˆ’h11550h8+4200h6âˆ’756h4+56h2âˆ’1) where P is the sagitta as a function of a normed radial distance h from an optical axis: h=distance&it;â€ƒ&it;from&it;â€ƒ&it;the&it;â€ƒ&it;optical&it;â€ƒ&it;axis12&it;(lens&it;â€ƒ&it;diameter&it;â€ƒ&it;of&it;â€ƒ&it;the&it;â€ƒ&it;aspheric)=normed&it;â€ƒ&it;radius0<h&leq;1â€ƒand wherein at least two of the following conditions are fulfilled: &LeftBracketingBar;K16K9&RightBracketingBar;<0.7(a)&LeftBracketingBar;K25K9&RightBracketingBar;<0.1(b)&LeftBracketingBar;K36K9&RightBracketingBar;<0.02(c)â€ƒthe radius of the aspheric lens surface being fixed so that K4=0.