TCST2103 Large U-Shaped Optical Sensor – Slot Encoder Module

Product Description

The TCST2103 is a transmissive optical sensor featuring an infrared emitter and a phototransistor positioned opposite each other inside a U-shaped slotted housing. When an object passes through the slot, it interrupts the infrared beam, allowing the sensor to detect movement or the presence of an object.

This makes the TCST2103 particularly suitable for optical switching, pulse counting, position detection, and encoder applications. The sensor is manufactured by Vishay and uses a 950nm infrared emitter with a phototransistor output.

Key Features

• U-shaped transmissive optical sensor.
• Integrated infrared emitter and phototransistor.
• Infrared wavelength: 950nm.
• Slot gap: 3.1mm.
• Aperture width: 1mm.
• Phototransistor output.
• Built-in daylight-blocking filter.
• Suitable for optical switching and pulse counting.
• Suitable for encoder and position-detection applications.
• Through-hole leaded package.

Technical Specifications

The key dimensions and electrical characteristics above are based on the manufacturer’s documentation and distributor specifications. (vishay.com)

Applications

• Optical encoders.
• Pulse and rotation counting.
• Position detection.
• Optical switches.
• Photo-interrupter applications.
• Object detection.
• Motor speed measurement.
• Mechanical movement detection.
• Electronic and automation projects.

How It Works

The TCST2103 contains an infrared LED and phototransistor facing each other across the sensor’s slot. When a rotating encoder disk, mechanical tab, or other object passes through the slot, it interrupts the infrared beam. The resulting change at the phototransistor output can be used by a microcontroller or electronic circuit to detect movement, count pulses, or determine rotational position.

Important Note

The TCST2103 is the sensor component itself, not a complete Arduino-style sensor module with signal-conditioning electronics. Additional circuitry may be required to interface its phototransistor output directly with a microcontroller, depending on the application.