NOVELTY - An optical device comprises a nitrogen and gallium containing substrate having a surface region, an n-type gallium nitride material overlaid on the surface region, an n-type gallium nitride material that overlaid on the surface region, an indium-aluminum-nitride material or a low gallium content containing indium-aluminum-gallium-nitride material configured as an optical blocking region that overlaid on the n-type gallium-nitride material, an n-type cladding region, a high indium content or thick indium-gallium-nitride region, an active region and a p-type cladding region.    USE - Optical device such as laser diode, laser, light emitting diode, solar cell, photoelectrochemical water splitting and hydrogen generation, photodetector, integrated circuit, and transistor.    ADVANTAGE - The optical device has better photoluminescence, electroluminescence and efficiency, and can be manufactured in a cost effective manner.    DETAILED DESCRIPTION - An optical device comprises a nitrogen and gallium containing substrate having a surface region, an n-type gallium nitride material that overlaid on the surface region, an n-type gallium nitride material that overlaid on the surface region, an indium-aluminum-nitride material or a low gallium content containing indium-aluminum-gallium-nitride material (INyAl1-x-yGaxN) configured as an optical blocking region that overlaid on the n-type gallium-nitride material, an n-type cladding region overlaid on the optical blocking region, a high indium content or thick indium-gallium-nitride region overlaid on the n-type cladding region, an active region overlaid on the high indium content or thick indium-gallium-nitride region and a p-type cladding region that overlaid on the active region, where the surface region is in a non-polar or semi-polar orientation, x is less than 30%, the optical blocking region is substantially lattice matched with the nitrogen and gallium containing substrate, the optical blocking region has a refractive index lower than that of the n-type cladding region, and the high indium content or thick indium-gallium-nitride region has refractive index higher than that of the n-type cladding region, and the optical device is free from aluminum-gallium-nitride and indium-aluminum-gallium-nitride cladding regions.