A semi-transparent screen with hemisphere micro-patterns was proposed and designed to enhance the brightness uniformity of the display image toward the driver for a direct-view type head-up display. The hemisphere micro-patterns were designed to consider the inclined angle of the windshield for efficient reflection and scattering toward to the driver. The density and radius of the hemisphere micro-patterns were adjusted as a function of position on the screen based on the geometrical calculation and analyzed by the commercial optical simulation tool based on a ray-tracing method. The designed hemisphere micro-patterns was fabricated by the thermal reflow method and evaluated to confirm the uniform illumination. From the results, the semi-transparent screen with variable micro-patterns shows the 91.9 % of brightness uniformity with the enhanced luminance compare to a screen without micro-patterns. A luminance of fabricated screen also shows good agreement with the simulation result to reflect the clear and bright driving information to the driver.
Bibliographical noteFunding Information:
This work was supported by the Industrial Technology Innovation Program (No. 10047785) and the Industrial Strategic Technology Development Program (No. 10035274) funded by the Ministry of Trade, Industry & Energy of Korea.
© 2015, The Optical Society of Japan.
All Science Journal Classification (ASJC) codes
- Atomic and Molecular Physics, and Optics