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. 26, 1991
Filed:
Mar. 23, 1990
Imax Systems Corporation, Toronto, CA;
Abstract
An alternate eye 3-d projection system has a projector projecting alternate eye left and right images, has alternating eye 3-d glasses alternating between left and right lens transmissiveness, and has a phase delay unit synchronizing the left lens transmissiveness to left images and right lens transmissiveness to right images. A timing shutter is driven through a mechanical link to the projector primary mechanism at a frequency proportional to the frequency of the transition between images. A sensor outputs pulses according to the rotationally frequency of the timing shutter. The phase delay unit receives the pulses, a multiplier multiplies the frequency of the pulses, a phase lock loop locks on to the frequency and a counter counts the pulses. After a preset delay the counter outputs a pulse. The delay is adjustable. The counter pulse enables a 60 KHz oscillator. The oscillations are counted by another counter and passed to a transmitter. The 60 KHz oscillations are disabled when the other counter reaches a preset amount. The other counter sets the duty cycle of the transmitter. Each of the components in the unit is duplicated in a back-up section. The back-up section is enabled when the primary phase lock loop is not locked on and the back-up phase locked loop is locked on.