The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 27, 2008
Filed:
Jun. 17, 2003
Mitsunori Toyoda, Sendai, JP;
Mitsunori Toyoda, Sendai, JP;
Nikon Corporation, Tokyo, JP;
Abstract
An optical integrator having characteristics to reduce effects of manufacturing errors of many minute refraction surfaces integrally formed by, for example, etching on an illumination intensity distribution. An optical integrator () comprising an integrally formed plurality of first minute refraction surfaces () and an integrally formed plurality of second minute refraction surfaces (). A parameter β satisfies conditions, |β|<0.2 (where β=(γ−1)·NA/Δn), where a refracting power ratio φa/φb between φa, a refracting power of the first minute refraction surfaces and φb, a refracting power of the second minute refraction surfaces is γ, numerical aperture on an emission side of the optical integrator is NA, and a difference between a refraction index of a medium on a light entrance side of the second minute refraction surfaces and a refraction index of a medium on a light emission side of the second minute refraction surfaces is Δn.