How to choose between photoelectric sensor and ultrasonic sensor in the technology difference?

In recent years, there has been a growing demand from customers for machine solutions that handle the sensing of heterogeneous materials. ultrasonic level transducers use the time-of-flight principle, and other industrial technologies such as inductive and photoelectric sensors are blank.

1. How to choose photoelectric sensor and ultrasonic sensor?

Each sensing technology has its own strengths and weaknesses. Photoelectric sensors are great for detecting objects within a few meters, but they may not be able to reliably sense black objects, and there is a risk that artificial lighting or sunlight may interfere with the sensing. Ultrasonic transducer sensors can sense objects up to several meters long, regardless of color or lighting conditions, but they are weak at sensing sound-absorbing materials. Even with these known weaknesses in both technologies, there are economical solutions, such as reflection mode or background suppression mode, that can detect objects efficiently.

2. You mentioned the flight time principle. Can you explain it a bit more?

An ultrasonic sensor sends out a series of ultrasonic pulses and calculates the time it takes for the echo to bounce off an object and return. The sensor uses the speed of sound to calculate the distance to an object. The technology is comparable to sonar technology used in submarines. Historically, photoelectric sensors were used for simple object detection, but today, there are applications of photoelectric sensors for distance measurement using the battle-time principle.

3. What is the difference between an ultrasonic sensor and a photoelectric sensor using the time-of-flight principle?

The time-of-flight photoelectric sensor has a small, bright laser spot that can sense small objects or objects with high incident angles. They feature fast response times and virtually zero dead zones. Some typical applications include detection of fast-moving packages or labels and precise position control of cranes. In contrast, an ultrasonic sensor has a 3-dimensional detection area - shaped like a cone - which makes it ideal for area detection. In addition, they can detect transparent objects, black objects and many liquids. Level measurement of liquids or solids, transparent bottle detection and collision detection are typical applications of ultrasonic sensors.