Local dimming on light-emitting screens for improved image uniformity in scanning beam display systems

A display system, comprising:

• light sources that produce optical beams at optical wavelengths in a violet spectral range or ultra violet (UV) spectral range;
• a signal modulation controller in communication with the light sources to cause the optical beams to be modulated in form of a time domain signal modulation as optical pulses that carry images to be displayed;
• a screen that receives the optical beams to display images carried by the optical beams and includes light-emitting regions that absorb light of the optical beams to emit visible light forming the images and one or more reference marks to produce feedback light from the screen from the illumination of the optical beams;
• an optical scanning module that scans optical beams onto the screen to transform, via spatially scanning each optical beam along a scanning path on the screen, the time domain signal modulation in each optical beam into spatial images on the screen;
• a designated optical detector located off the screen can to collect the optical feedback light from the screen to convert the collected optical feedback light into a detector signal that contains position information of each optical beam on the screen;
• wherein the signal modulation controller receives the detector signal from the designated optical detector and operates to control the light sources, based on the time domain signal modulation and the position information of each optical beam on the screen in the received detector signal, to adjust optical energies of the optical pulses of the optical beams with respect to positions of the scanning optical beams on the screen to render the images on the screen via spatially scanning each optical beam on the screen, and
• wherein the signal modulation controller, in addition to adjusting optical energies of the optical pulses for transforming, via spatially scanning each optical beam along a scanning path on the screen, the time domain signal modulation in each optical beam into spatial images on the screen, adjusts optical energies of the optical pulses of at least one optical beam, based on information of a predetermined spatial variation of each optical beam in connection with the location of the optical beam on the screen caused by one or more distortions in scanning the optical beam onto the screen, to reduce the one or more distortions in the images displayed on the screen.