Title:
広角可変式中性濃度フィルタ
Document Type and Number:
Japanese Patent JP7263643
Kind Code:
B2
Abstract:
A three (or more) polarizer arrangement is used to demonstrate a wide-angle variable-neutral-density (VND) filter that has both contrast uniformity and color uniformity. According to one embodiment, the outer polarizers effectively counter-rotate with respect to a fixed center polarizer as a means of compensating for transmission non-uniformity associated with geometrical polarization distortions experienced by off-normal rays. In particular, the achromatic compensation arrangement enables angle uniformity relative to normal-incidence transmission when the number of stops of attenuation grows large (e.g. 10-stops, or OD3). The filters are useful for cameras or instrumentation allowing mechanical or electromechanical tuning.
Inventors:
Sharp, Gary Dee
McGettigan, Anthony Dee
McGettigan, Anthony Dee
Application Number:
JP2019570347A
Publication Date:
April 25, 2023
Filing Date:
March 08, 2018
Export Citation:
Assignee:
META PLATFORMS TECHNOLOGIES, LLC
International Classes:
G02B26/02; G02B5/28; G02B5/30; G02B27/28; G03B11/00
Domestic Patent References:
| JP2010128329A | ||||
| JP2008309893A | ||||
| JP2006284852A | ||||
| JP2009237202A | ||||
| JP2014123076A | ||||
| JP2014191346A | ||||
| JP11277668A | ||||
| JP2015055737A | ||||
| JP2010113255A | ||||
| JP2000356770A | ||||
| JP2014506337A | ||||
| JP2008533524A | ||||
| JP2016046771A | ||||
| JP2001251554A | ||||
| JP2013521706A |
Foreign References:
| US4202601 | ||||
| US20160259103 | ||||
| US5337191 |
Attorney, Agent or Firm:
Patent Attorney Corporation World IP