1. Overview

Slot-type photointerrupters with logic output are optoelectronic sensors consisting of a light emitter (usually infrared LED) and a photodetector (phototransistor or photodiode) aligned in a U-shaped housing. When an object interrupts the light beam between the slot, the sensor generates a logic-level output signal. These devices are critical in industrial automation, consumer electronics, and medical equipment for position detection, motion control, and object counting.

2. Main Types & Functional Classification

3. Structure & Components

Typical construction includes: - Infrared LED emitter (850-940nm wavelength) - Phototransistor detector with built-in amplifier - Plastic housing forming mechanical slot (0.5-10mm width) - Integrated circuit for signal conditioning - Lead frame for PCB mounting (through-hole or SMD)

4. Key Technical Specifications

5. Application Fields

• Industrial automation: Conveyor belt object counting
• Office equipment: Paper jam detection in printers
• Medical devices: Syringe pump position verification
• Consumer electronics: Appliance door interlock systems
• Automotive: Gear position detection in transmission systems

6. Leading Manufacturers & Products

7. Selection Guidelines

Key considerations: - Required slot width vs target object dimensions - Environmental factors (dust, vibration, temperature) - Electrical compatibility with host system - Mechanical mounting constraints (through-hole vs SMD) - Required detection speed and output response time - EMI/RFI immunity for industrial environments

8. Industry Trends

Current developments include: - Miniaturization for mobile device integration - Smart sensors with embedded diagnostics - Wireless-enabled models for IoT applications - Improved optical efficiency through GaAlAs LEDs - Multi-channel integration for parallel detection