New IR LED for iris scanners
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The new SFH 4786S also has another special feature. It predecessor SFH 4780S was optimized for maximum light output, and the new version has an extra lens system that tilts the emitted light beam at an angle of 8 degrees to the vertical axis. This tilted emission pattern concentrates the light in the field of view of the iris camera, which it is always mounted slightly offset from the IR LED. That makes the performance of the overall system significantly better than with a LED that has a vertical emission pattern. Previously mechanical aids were used to get the right alignment. With the SFH 4786S they are no longer necessary, reducing the complexity of the complete system. In addition, the new IR LED has a somewhat broader emission angle of ±13 degrees to illuminate a larger area at the typical working distance of iris scanners.
The SFH 4786S emits IR light at a wavelength of 810 nm, the same as its predecessor. High-resolution images of all iris colors can be achieved in this spectral region. The chips have a nanostack structure with two emission centers per emitter, which maximizes the optical output.

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