*Blue Laser Diode-Based Visible Light Communication and Solid-State Lighting DOI: http://dx.doi.org/10.5772/intechopen.100106*

between LEDs and LDs are shown in **Figure 2(a)**. The efficiency of LEDs is high at a relatively low input current density and decreases with the increasing input current density. In contrast to LEDs, the LDs efficiency is low at low input current density and keeps rising with input current density after threshold current. At higher current densities, the efficiency of the LDs eventually drops because of resistivity loss.
