Two open can diodes?

[busterhax]

So i opened up a random dvd burner at work today. The burner had the "label flash" feature. Anyways, i found two open can diodes on the sled. I was curous why there are two diodes for this?

 

[jonrobertd]

1 red and 1 IR Laser. Open can red for DVD and open can IR for CD.