Many optical applications require the use of broadband light sources such as our arc or QTH lamps. However, often during the setup or testing phases of an experiment the lamp’s light is not necessary as it could be damaging to the user or sample under test. Frequently igniting the lamp or toggling its power supply are not practical solutions for blocking the light as these actions cause added strain and can drastically reduce the lamp’s lifetime. Instead, these low light leakage shutters offer a simple solution to blocking the output path of a lamp housing when light output is not needed. These shutters can be used to allow the lamp to warm-up while the user configures their equipment, let the user make minor adjustments to the setup throughout testing, or permit the user to change samples under test all without disturbing the lamp’s internal function. When using arc lamps, these shutters are recommended to block the user or sample from unnecessary UV radiation exposure.

Radiometric zeroing is the process of defining a negative offset when light is not incident on a photodetector. This process is used in practice to filter background noise from the detector and associated electronics when taking light measurements. These low light leakage shutters offer a simple way to "zero" a photodetector.