Invention Grant
- Patent Title: Video projection apparatus capable of realizing stable rocking angle at optimum resonant frequency
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Application No.: US15294444Application Date: 2016-10-14
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Publication No.: US10080001B2Publication Date: 2018-09-18
- Inventor: Takao Saito
- Applicant: STANLEY ELECTRIC CO., LTD.
- Applicant Address: JP Tokyo
- Assignee: STANLEY ELECTRIC CO., LTD.
- Current Assignee: STANLEY ELECTRIC CO., LTD.
- Current Assignee Address: JP Tokyo
- Agency: Holtz, Holtz & Volek PC
- Priority: JP2015-212152 20151028
- Main IPC: H04N9/31
- IPC: H04N9/31 ; G02B26/08 ; G02B26/10 ; G02B26/12

Abstract:
A video projection apparatus includes: an optical deflector having a mirror projecting a first view field and projecting a second view field, an actuator for rocking the mirror and a sensor; an optical guide unit provided within the second view field; a photodetector; and a control unit. The control unit is adapted to calculate a resonant frequency of the sinusoidal-wave voltage; detect a first timing point from a sense voltage; detect a second timing point from a photo detection voltage when the second light beam is incident to the optical guide unit; calculate a time period from the first timing point to the second timing point; calculate a product value between the time period and the resonant frequency; and control an amplitude of the sinusoidal-wave voltage.
Public/Granted literature
- US20170127033A1 VIDEO PROJECTION APPARATUS CAPABLE OF REALIZING STABLE ROCKING ANGLE AT OPTIMUM RESONANT FREQUENCY Public/Granted day:2017-05-04
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