Application Example (1-09)
Dental Clinical Unit

Application Example (1-09)

Dental Clinical Unit

Touchless switch (sensing of hand)


  • ・Turn on/off the illumination in a touchless manner by sensing the hand.

Issues & Requests

  • ・Want to change the switch to the touchless type from the viewpoint of sanitation and adopt an easy-to-clean structure.
  • ・Want to ensure detection of the palm by the sensor.
  • ・Want to eliminate the sensor’s malfunction due to external disturbing light.

General sensors may not be able to detect the hand. In addition, the sensor may unintentionally sense a distant object.
Since the sensor is installed toward the outside of the equipment, it may malfunction due to the incident external disturbing light such as sunlight and illumination.


  • ・Adopted model:
    Light convergent reflective sensor B5W-LB2112-1
  • ・This sensor is optically designed to detect objects such as specular, black, and transparent objects.
    Therefore, it is effective for detecting the palm.
  • ・Because the sensing distance is limited, malfunctions caused by unintended distant objects can be avoided.
  • ・By placing a thin transparent cover on the front of the sensor and flattening it, it is possible to design equipment with a drip-proof structure that is easy to clean.
  • ・This sensor has a function that makes it less susceptible to disturbance light via light. However, it may malfunction depending on the type and intensity of the light disturbance, so install a sensor to prevent the light disturbance from entering. 

For details, refer to B5W-LB Series: Light Convergent Reflective Sensor User’s Manual.

  • Distance Characteristics for
    Various Reflective Objects
  • Receiver Output-Sensing Distance

*The possibility of detecting the object varies depending on the sensing object or how to install the sensor.
Be sure to conduct sufficient evaluation using the actual devices before staring practical use.

Recommended models: