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:
Jan. 26, 1982
Filed:
May. 01, 1980
Sony Corporation, Tokyo, JP;
Abstract
An inline hologram lens suitable for use in an optical reproducing head is formed by first preparing a mother off-axis hologram lens by exposing a photo-sensitive layer to a subject wave beam and an off-axis reference wave beam, and then developing the photo-sensitive layer; and subsequently by forming the inline hologram lens by exposing a second photo-sensitive layer to an interference pattern formed by passing an inline reference wave beam through the mother off-axis hologram lens to be incident normal to the second photo-sensitive layer while passing an off-axis subject coherent beam at an angle through said off-axis mother hologram lens to form a subject beam that is focussed a predetermined distance from the second photo-sensitive layer, and finally by developing the second photo-sensitive layer. Preferably, the mother hologram lens has a diffraction efficiency of less than unity. An optical reproducing head utilizing such an inline hologram lens includes a beam-splitter, a quarter-wave plate, the inline hologram lens, and a transparent adhesive to adhere the beam-splitter, plate, and lens to one another.