Projection synchronization system
US5002387A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1990 |
| Grant date | Mar 26, 1991 |
| Priority date | — |
| Expiry date | Mar 23, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N13/398
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
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 w…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.