| CPC G02B 6/4214 (2013.01) [G02B 6/4206 (2013.01); G02B 6/4242 (2013.01); H01L 25/167 (2013.01); H01L 31/0203 (2013.01)] | 21 Claims |

|
1. An apparatus comprising:
a photodetector (PD) die comprising:
an optical element formed on a first side of the PD die; and
a photodetector disposed on a second side of the PD die, the first side opposite the second side, wherein the photodetector is disposed on the second side of the PD die offset from an optical axis of the optical element,
wherein the optical element comprises a sag and a clear aperture, wherein a ratio of sag to clear aperture is less than 1:10.
|