Light Wave Spectrum: Light Wave Spectrum - In everyday terms, light can be defined as the pail of the visible spectrum that has a wavelength range between 0.4 μm (micrometer) and 0.7 μm (refer to…
Light Units: The total light energy output, or luminous flux (Φs), from a source can be measured in milliwatts (mW) or in lumens (1m), where 1 Im = 1.496 mW. The luminous intensity (Es) (also…
Light Emitting Materials: Since the eye is only sensitive to light of energy hf ≥ 1.8 eV (~ 0.7 μm), semiconductors of interest must have energy band gaps larger than this limit. The band gaps of…
Light Dependent Resistors (LDRs) - Definition, Construction, Workings and Applications: Light dependent resistors (LDRs) are made from cadmium sulphide containing no or very few free electrons when not illuminated. Its resistance is then quite high.…
Light Activated SCR (LASCR) - Symbol, Construction and Operation: Light activated SCR is just an ordinary SCR except that it can also be light triggered. Most LASCRs also have a gate terminal for beÂing triggered…
Level Detector: Schmitt trigger or level detector circuits are very often employed in static relay circuits as a final stage before the trip coil circuit of the circuit breaker. The name level detector is derived…
Lens Antenna Design: The paraboloid reflector is one example of how optical principles may be applied to microwave lens antenna, and the Lens Antenna is yet another. It is used as a collimator at frequencies…
LED Seven Segment Display: The arrangement of a LED Seven Segment Display is shown in Fig. 20-6(a). The actual LED devices are very small, so, to enlarge the lighted surface, solid plastic light pipes are…
Least Square Estimation Method: As we are going to seen that, the problem of power system state estimation is a special case of the more general problem of estimation of a random vector x from…
Leakage Current in a Transistor and Breakdown Voltage: Leakage Currents: In CB circuits shown in Fig. 10.77, if emitter current is made zero, the B-C junction still remains reverse biased and therefore, a reverse-bias leakage…
