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:
Mar. 15, 2022
Filed:
May. 18, 2018
Dispelix Oy, Espoo, FI;
Mika Aikio, Espoo, FI;
Dispelix Oy, Espoo, FI;
Abstract
The invention concerns a projection objective and a waveguide display. The objective is adapted to project an image from a first plane to a second plane and comprises in order from the second plane a first optical element group having a positive effective focal length, a second optical element group placed between the first plane and the first optical element group and having a negative effective focal length, and a third optical element group placed between the first plane and the second optical element group and having a positive effective focal length. Counting from the second plane, the first refractive surface of the second optical element group is concave towards the second plane and the second refractive surface of the third optical element group is convex towards the first plane. The objective suits well for projecting images to diffractive optical displays.