Since pico-projectors were starting to become the next electronic "must-have" gadget, the experts were discussing which
light-source technology seems to be the best for the existing three major projection approaches for the optical scanning
module such as digital light processing, liquid crystal on silica and laser beam steering. Both so-far used light source
technologies have distinct advantages and disadvantages. Though laser-based pico-projectors are focus-free and deliver a
wider color gamut, their major disadvantages are speckle noise, cost and safety issues. In contrast, projectors based on
cheaper Light Emitting Diodes (LEDs) as light source are criticized for a lack of brightness and for having limited focus.
Superluminescent Light Emitting Diodes (SLEDs) are temporally incoherent and spatially coherent light sources
merging in one technology the advantages of both Laser Diodes (LDs) and LEDs. With almost no visible speckle noise,
focus-free operation and potentially the same color gamut than LDs, SLEDs could potentially answer the question which
light source to use in future projector applications. In this quest for the best light source, we realized visible SLEDs
emitting both in the red and blue spectral region. While the technology required for the realization of red emitters is
already well established, III-nitride compounds required for blue emission have experienced a major development only
in relatively recent times and the technology is still under development. The present paper is a review of the status of
development reached for the blue superluminescent diodes based on the GaN material system.