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If a particular optical power is coupled from an incoherent LED into a low-NA fiber, the device must exhibit very high radiance.

If a particular optical power is coupled from an incoherent LED into a low-NA fiber, the device must exhibit very high radiance. Correct Answer True

Device must have very high radiance specially in graded index fiber where Lambertian coupling efficiency with same NA is about half that of step-index fibers. This high radiance is obtained when direct bandgap semiconductors are fabricated with DH structure driven at high current densities.

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