What are the output states for a Light Diffuse photo detector when the target is absent?

When considering the operation of a Light Diffuse photo detector, it is important to understand its functionality in detecting light. When a target is absent, the device relies on the emitted light from the source to determine the presence or absence of the target.

In the scenario where the target is not present, the light emitted from the sensor will not be reflected back to the detector. This lack of reflected light leads to the detection output from the sensor, specifically the transmitted beam, being in an 'OFF' state. The transmitted beam being 'OFF' signifies that the photo detector is not receiving any light, as there is no reflective surface to return the light signal.

Thus, the correct identification of the output state when the target is absent is that the transmitted beam is 'OFF.' Understanding this principle of light reflection and detection is crucial in applications like sensing, which rely on the interaction of light with objects in their environment.