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. 06, 2025
Filed:
Oct. 28, 2020
Takashi Kamitakahara, Tokyo, JP;
Ken Shirasaki, Tokyo, JP;
Mutsumi Tanifuji, Tokyo, JP;
Hayato Yoshida, Tokyo, JP;
Takashi Kamitakahara, Tokyo, JP;
Ken Shirasaki, Tokyo, JP;
Mutsumi Tanifuji, Tokyo, JP;
Hayato Yoshida, Tokyo, JP;
RICOH COMPANY, LTD., Tokyo, JP;
Abstract
A projection lens system (G, G) includes a front group (G) disposed on a projection-plane (SC) side, a rear group (G) disposed on a display-surface (SF) side of an image display element inclined with reference to the projection plane (SC), and an aperture stop (S) disposed on the display-surface (SF) side with reference to the front group (G). The rear-group optical axis is tilted on the shared plane at a tilt angle ξ with reference to the display-surface normal. In projection lens system (G, G), when the amount of shift Δ is zero, the tilt angle ξ satisfies a conditional expression 0<ξ/ξs<1, where ξs denotes a tilt angle when Scheimpflug principle is satisfied with reference to the display surface (SF) and the projection plane (SC).