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Currently, a 445 nm LD (PL TB450) with 1.4 W of output power is commercially available from OSRAM. With an efficiency of 24.3% and a cw operational lifetime of over 30 000 h, this was an important milestone in high power ~445 nm LD development. reported an LD diode operating at 445 nm with continuous wave (cw) output power of 1.17 W under a steady current of 1.0 A with 4.81 V of bias voltage. Researchers worldwide focused on longer wavelengths towards ‘true blue’ or ‘royal blue’ (~445 nm) for digital displays and solid state illumination purposes. This LD offered 215 mW of output power under pulsed current (2.3 A, pulse width 2 μs, pulse period 2 ms). The first milestone towards blue LD development was achieved by Nakamura with the demonstration of a multi-quantum well (MQW) based InGaN LD operating at violet blue (417 nm). High luminous flux, compact size and low power consumption are very important features for designing light engines for multimedia projectors and automotive headlamps, and hence LDs have an advantage over LEDs in such applications. Blue LD and phosphor based white light engines are already integrated in various commercial multimedia projectors. Naturally, there has also been an enormous interest in developing efficient high power LDs operating at visible (RGB) wavelengths. reported high power 940 nm LDs with electrical-to-optical power conversion efficiency as high as 76%. In near infrared (NIR), LDs are the most efficient high power sources of photons, in terms of electrical-to-optical power conversion. Laser diodes (LDs) are inherently much brighter than LEDs. The combination of the remaining blue component and the frequency down-converted wide spectrum, ranging from green to red, is what we see as ‘white’ light output from such an LED. A part of the blue light is absorbed by phosphor which generates a wide range of wavelengths between green and red due to phosphorescence. Most of these white LEDs are basically made of a 445–460 nm blue emitting LED chip with a coating of yellow phosphor. White light-emitting diodes (LEDs) are currently widely used in the SSL domain. Solid-state lighting (SSL) has revolutionized the illumination situation and is steadily progressing in terms of power efficiency and diversity for future applications.