Raster shifting delay compensation system
First Claim
1. An apparatus for compensating for angular displacement of a visual scene from a helmet mounted projector, said projector utilizing a raster scan having distinct vertical and horizontal scan means to project said visual scene generated by a computer image generator in accordance with positional data output by a pilot look direction tracker, comprising in combination:
- means for interfacing with said tracker to receive positional data therefrom, said interfacing means having storage capacity for said data and output for said data,means for determining compensatory angular displacement values based on iterative comparisons of said positional data, including a microprocessor, operably connected to receive data from said interfacing means and to output said displacement values, said microprocessor having inputs for receiving instructions, memory means containing instructions for said microprocessor operably connected thereto for providing thereto said instructions, and memory means for storage of positional data and initial condition data for processing by said microprocessor operably connected thereto for providing said data to said microprocessor;
means for inputting displacement values into said horizontal and vertical scan means operably connected to receive said values from said determining means;
means for inputting said positional data to said CIG operably connected to said interface means; and
means for synchronizing said value input means with said CIG, thereby presenting continuous display operably connected to said CIG data input means, value input means, said determining means, said interface means, and said tracker.
1 Assignment
0 Petitions
Accused Products
Abstract
A compensation system for use in a helmet mounted raster projection systemtilizes a microprocessor to control the offset position of the raster line and frame scanners, thereby increasing the stability of the viewed scene. The microprocessor calculates control words which are fed to the scanners via digital to analog converters during the vertical sync of the raster scan. The microprocessor calculates the control words from pilot look data obtained by head and eye trackers compared to previous similar data.
14 Citations
14 Claims
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1. An apparatus for compensating for angular displacement of a visual scene from a helmet mounted projector, said projector utilizing a raster scan having distinct vertical and horizontal scan means to project said visual scene generated by a computer image generator in accordance with positional data output by a pilot look direction tracker, comprising in combination:
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means for interfacing with said tracker to receive positional data therefrom, said interfacing means having storage capacity for said data and output for said data, means for determining compensatory angular displacement values based on iterative comparisons of said positional data, including a microprocessor, operably connected to receive data from said interfacing means and to output said displacement values, said microprocessor having inputs for receiving instructions, memory means containing instructions for said microprocessor operably connected thereto for providing thereto said instructions, and memory means for storage of positional data and initial condition data for processing by said microprocessor operably connected thereto for providing said data to said microprocessor; means for inputting displacement values into said horizontal and vertical scan means operably connected to receive said values from said determining means; means for inputting said positional data to said CIG operably connected to said interface means; and means for synchronizing said value input means with said CIG, thereby presenting continuous display operably connected to said CIG data input means, value input means, said determining means, said interface means, and said tracker. - View Dependent Claims (2, 3, 4, 5)
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6. An apparatus for compensating for angular displacement of a visual scene from a helmet mounted projector, said projector utilizing a raster scan having distinct vertical and horizontal scan means to project said visual scene generated by a computer image generator in accordance with positional data output by a pilot look direction tracker, comprising in combination:
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means for interfacing with said tracker to receive positional data therefrom, said interfacing means having storage capacity for said data and output for said data; means for determining compensatory angular displacement values based on said positional data, said determining means operably connected to receive data from said interfacing means, and outputting said displacement values, including a microprocessor, operably connected to receive data from said interfacing means and to output data, as displacement values, said microprocessor having inputs for receiving instructions, memory means containing instructions for said microprocessor operably connected thereto for inputting said instructions, and memory means for storage of positional data and initial condition data for processing by said microprocessor operably connected thereto for providing said data to said microprocessor; means for inputting displacement values into said horizontal and vertical scan means operably connected to receive said values from said determining means, including a first digital to analog converter inputting said displacement value into said horizontal scan means, a second digital to analog converter inputting said displacement value into said vertical scan means, and bus means operably connecting said first and second DAC to said interfacing means; means for inputting said positional data to said CIG operably connected to said interface means, including data buffer means receiving positional data input from said interfacing means, transparent to the operation of said determining means, and outputting positional data to said CIG; and means for synchronizing said value input means with said CIG, thereby presenting continuous display operably connected to said CIG data input means, value input means, said determining means, said interface means, and said tracker.
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7. A method of compensating, under microprocessor control, for angular displacement of a visual scene due to processing delays in a projection system utilizing a helmet mounted projector to display a raster scan image generated by a computer generated imaging system in accordance with positional data supplied by a pilot look direction tracking unit, comprising the steps of:
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aligning said helmet mounted projector'"'"'s axis of projection for zero offset; iteratively sampling head position data by said tracking unit during each field of said raster scan; outputting serial data corresponding to said head position data from said tracker; converting said serial data to parallel data; storing said position data in a memory table; comparing the most recent head position data with preselected position data stored in said memory from a previous field to determine changes in head position; computing of set values for said raster projection axis for compensating for said head motion; sending head position data to said CIG during each field; varying said raster projection axis in accordance with said offset values; and synchronizing the above steps such that said raster offset is varied during a raster return time whereby said visual presentation is not disrupted. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14)
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Specification