A sound deflector is a tool that you can use with your ultrasonic sensors. An ultrasonic sensor detects and measures by using ultrasonic soundwaves. This beam of sound waves is also called a sound pulse or sound cone. The sensor head (or transducer) emits and receives this sound. When this sound is reflected; a detection and/or measurement is performed. In some situations the sensor cannot emit sound straight ahead. In that case a sound deflector is needed.
In a regular mounting, an ultrasonic sensor emits its sound straight forward and makes it reflect from a medium or object. When you are dealing with, for example:
- Insufficient mounting space;
- Chemicals;
- High temperatures;
- Condensation / moist build-up;
- Or sparks and/or splashes,
the sensor is can not be mounted right above the object/medium. This is because these applications can have a negative effect on the sensor head. The solution is a sound deflector.

Sound deflector: guide the sound to your measurement or detection

The solution for aforementioned situations is the sound deflector from microsonic for ultrasonic sensors. The deflector has a hole on one side where an ultrasonic with a cylindrical screw thread housing (sizes: M18/M30) can be mounted in. When the sensor is mounted, the sensor "looks" at a tilted metal plate, this is the deflector plate. This plate deflects the sound in a 90° angle. This prevents the sensor head from getting into direct contact with the target, condensations, splashes, sparks, etc.
How an ultrasonic sensor with sound deflector works:
- The sensor emits a sound wave.
- The sound wave hits the tilted plate of the deflector.
- The sound wave is deflected in an angle of 90°.
- The deflected sound wave reaches the target that has to be measured or detected.
- The deflected sound wave is reflected from the target and comes back to the deflector.
- The deflector bends the sound wave back to the sensor, so the received sound can be processed by the ultrasonic sensor.
- This process repeats itself, based on the switching frequency of the sensor.
When do you use a sound deflector for your ultrasonic sensor?
Insufficient mounting space was first mentioned as an example of an application in the introduction to this article. The mounting in a 90° angle, combined with a deflector plate saves space. Below, we sum up a number of applications that can be bridged with the use of a deflector as well:
Detection of glowing hot metals

The sensor can, because of the temperature of the metal, not be mounted right above the application. By using a deflector, the sensor can be used without risking melting it by the temperature of the metals. The use of a deflector allows the metal plates or beams to be detected.
Level measurements of corrosive liquids in containers

In industries with heavy chemicals such as the cleaning agents industry it is possible to mount a chemical-resistant ultrasonic sensor, such as those from the pico+TF or crm+ series, can be placed right above a container with corrosive materials to perform level measurements. There are materials that are not covered by this chemical resistibility, therefore the use of a deflector is advised.
Transport systems with less or no monting space

A deflector provides a solution in a transport system without mounting space on the sides of the conveyor belt. By mounting the sensor to a nearby mounting point with a sound deflector it is possible to direct the sound wave to the conveyor belt and thus solve this space problem.