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The amount of radiance in planer type of LED structures is ____________

The amount of radiance in planer type of LED structures is ____________ Correct Answer Low

Planer LEDs are fabricated using liquid or vapor phase epitaxial processes. Here p-type is diffused into n-type substrate which creates junction. Forward current flow through junction provides Lambertian spontaneous emission. Thus, device emits light from all surfaces. However a limited amount of light escapes the structure due to total internal reflection thus providing low radiance.

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