The Model 346 lens was designed to utilise specially selected glasses with the least amount of yellow tint so that the image would be as natural as possible while still retaining non-browning performance in environments subject to radiation.
The Model 346 lens uses special glass that can withstand long-term exposure to radiation up to a dose of 100 million radians and temperatures to 55°C without discoloration. Operating up to f/2 it provides high image resolution and minimum geometric distortion from 400 to 750 nm, and it can image objects from 50mm to infinity without using add-on adapters. The Model 346 lens is designed for optimised use with 15mm diagonal colour CMOS sensors.
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