Patent ID: 8350208

Claim:
A photodetector module comprising, (i) one or an array of multi junction photodetectors (MJPDs), wherein each individual MJPD comprises (a) a first building block having a first bandgap; (b) an ultimate building block, having a second bandgap, positioned over or under the first building block; and (c) a tunnel diode between each of the building blocks; wherein the tunnel diodes have reversed polarity with respect to the building blocks; and wherein the building blocks are serially connected with the same polarization, and the first and second bandgaps are not identical; and wherein the first building block or ultimate building block comprises a detecting surface; (ii) a first light source having a first light spectrum that can be absorbed only by the first building block; and (iii) a second light source having a second light spectrum that can be absorbed only by the ultimate building block; wherein each light source is positioned to illuminate the detecting surface of the MJPDs.