Variable Attenuator for See-Through Day/Night Displays

In this SBIR Phase II proposal, Kent Optronics Inc proposes to develop a high performance variable light transmittance (VLT) attenuator prototype for head mounted see-through day/night displays, such as augmented reality (AR) displays. The attenuator can be universally fit into variety of AR displays based on waveguide, holographic, free-form, etc. The attenuator transmittance can be continuously varied from high for an unobscured view of the environment in low light level to low for maintaining high display contrast under extremely bright environment (2,000-fL). The attenuator can further be pixilated to locally attenuate bright spot(s) within the field of view (FOV).  The attenuator prototype will be integrated into selected AR displays for full compliance tests to reach TRL 6 and delivered to the government. The attenuator exhibits the following key remarkable features: Color neutral in the 400 -700 nm visible spectrum; Continuous transmission variation from £2% to ³80%; Power-fail clear with ³80% transmittance; Fast switching time of < 1 sec over -40 to 50 oC operation temperature; Monolithic form factor in compact size, weight, power consumption, and cost (SwaPC); Full compliance with ANSI Z87.1 standards.