The global source shutter in DEVICE can be used to investigate the transient response of a component to a light pulse (CHARGE) or a heat pulse (HEAT). In the CHARGE solver, the shutter can be used to turn on/off optical generation objects and in the HEAT solver, the shutter can be used to turn on/off heat sources to simulate the response of the device.
• SHUTTER MODE: disabled for no shutter, step on and step off for step functions, pulse on and pulse off for a pulse with on and off times. The time shutter function will be plotted as the option is chosen for ease of use. The on and off times can then be specified.
• SHUTTER TON: Sets the ON time of the shutter.
• SHUTTER TOFF: Sets the OFF time of the shutter.
• SHUTTER TSLEW: Sets a slew in the stepping of the shutter. This feature is useful in helping the solver to converge where a sharp step in the optical shutter tend to makes the solver diverge.
• SHUTTER SLEW FUNCTION: linear for a linear transition between off and on states, log for an exponential change between the off and on states. The log option uses the “shutter slew cutoff” value.
• SHUTTER SLEW CUTOFF: If the “log” option is selected for the shutter slew function, the shutter uses the logarithmic function to step from this value to 1 (for turning on) and from 1 to this value (for turning off). The switch from 0 to the cutoff value (and back) is abrupt and happens in a single time step.
• ILLUMINATION POWER SCALING: This option can be used to scale the amplitude of the source. By default the value is set to ‘1’ which means no scaling.