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:
Feb. 23, 1988
Filed:
Jun. 26, 1986
Kenichi Nishi, Tokyo, JP;
Hiroyoshi Rangu, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
An optical modulator for varying intensity, frequency, phase and other information associated with input light in response to a voltage which is applied thereto from outside is disclosed. The modulator comprises a semiconductor substrate, at least one semiconductor ultrathin layer which is thinner than an order of electron mean free path, and electrodes capable of applying an electric field to said ultrathin layer in a perpendicular direction to the layers. The band gap of narrow band gap layers in the ultrathin layer is spatially varied with respect to the perpendicular direction to the layers. The band gap of the narrow band gap layers is monotonously varied in the perpendicular direction to the layers. The ultrathin layer is interposed between a p-type semiconductor and an n-type semiconductor with respect to the perpendicular direction to the layers, a band gap of semiconductor layers in the ultrathin layer and having a narrow band gap being sequentially narrowed toward the p-type semiconductor layer. The band gap of semiconductor layers in the ultrathin layer and having a narrow band gap is largest in the vicinity of the center and sequentially reduced toward opposite ends.