If a particular optical power is coupled from an incoherent LED into a low-NA fiber, the device must exhibit very high radiance . State whether the given statement is true or false.

Related MCQs

• In a GaAs LED, compute the loss relative to internally generated optical power in the fiber when there is small air gap between LED and fiber core. (Fiber coupled = 5.5 * 10-4Pint)
• Estimate optical power coupled into fiber of DH SLED having emission area of 1.96*10-5, radiance of 40 W/rcm2, numerical aperture of 0.2 and Fresnel reflection coefficient of 0.03 at index matched fiber surface.
• The overall power conversion efficiency of electrical lens coupled LED is 0.8% and power applied 0.0375 V. Determine optical power launched into fiber
•  For many applications which involve optical fiber transmission, an intensity modulation optical source is not required. State whether the given statement is true or false.
• . A decibel may be defined as the ratio of input and output optical power for a particular optical wavelength. State whether the following statement is true or false.
• A planar LED is fabricated from GaAs is having a optical power emitted is 0.018% of optical power generated internally which is 0.018% of optical power generated internally which is 0.6 P. Determine external power efficiency.
• Stress corrosion must be considered while designing and testing optical fiber cables. State whether the given statement is true or false.
• Stress corrosion must be considered while designing and testing optical fiber cables. State whether the given statement is true or false.
• If the input power 100μW is launched into 6 km of fiber, the mean optical power at the fiber output is 2μW. What is the overall signal attenuation through the fiber assuming there are no connectors or splices?
• When a constant d.c. drive current is applied to device, the optical o/p power is 320 μm. Determine optical o/p power when device is modulated at frequency 30 MHz with minority carrier recombination lifetime of LED i.e. 5ns.