DLPA116 October   2020 DLP3021-Q1

 

  1.   Trademarks
  2. 1Static projection in automotive applications
  3. 2Brightness Requirements
    1. 2.1 Main Parameters that Influence Display Brightness
      1. 2.1.1 Ambient Lighting Conditions
      2. 2.1.2 Projection Surface Impact on Display Brightness
      3. 2.1.3 Size of the Displayed Image
      4. 2.1.4 Brightness of the Displayed Image
    2. 2.2 Other Brightness Considerations
      1. 2.2.1 Time of Day
      2. 2.2.2 Projector Contrast
      3. 2.2.3 Other Application Constraints
    3. 2.3 Brightness Capabilities with DLP Technology
  4. 3Summary
  5. 4References

2 Brightness Requirements

Projectors for automotive applications can have varying optical flux requirements, around 100 lumens for some augmented reality head-up display systems and over 1500 lumens for some high resolution headlight systems. Dynamic ground projector (DGP) applications also have varying flux requirements, but will typically be below 50 lumens. The main parameter that determines the required brightness in a DGP application is display size, but there are also several parameters that might restrict maximum brightness such as required mechanical form factor, required power limit, ambient brightness, or desired thermal performance.

There are two main units used to determine the brightness of a projector or a display. The optical flux of a projector is typically measured in lumens (lm), a measurement of the total light output of the projector, while the brightness, or luminance, of a display is typically measured in candela per meters squared (cd/m2), or nits. The relationship between luminance [cd/m2], illuminance [lux], and optical flux [lumens] are described in the equations below.