Hyper-Bright LED Lead (Pb) Free Product - RoHS Compliant # Technical Documentation: LSR 676 High-Speed Infrared Emitter
Manufacturer: OSRAM Opto Semiconductors
Component: LSR 676
Type: High-Speed, High-Power Infrared (IR) Emitter
Document Revision: 1.0
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## 1. Application Scenarios
The OSRAM LSR 676 is a GaAlAs double heterostructure infrared emitter designed for applications requiring high optical output power coupled with very fast switching capabilities. Its core design centers on a small emitting surface, enabling excellent modulation performance.
### Typical Use Cases
* High-Speed Data Transmission & Communication:
* IrDA (Infrared Data Association) Compliant Links: Ideal for implementing fast infrared data ports (e.g., IrDA 1.1 up to 4.0 Mbit/s) in laptops, PDAs, smartphones, and printers.
* Free-Air Optical Communication: Used in short-range, line-of-sight data links for secure point-to-point communication in industrial control systems or specialized networking equipment.
* Fiber Optic Transmitters: When coupled with a plastic optical fiber (POF), it serves as a highly efficient transmitter for industrial bus systems (e.g., PROFIBUS, DeviceNet) and automotive infotainment networks.
* Sensing and Detection Systems:
* Proximity & Presence Sensing: Integrated into devices like automatic faucets, soap dispensers, hand dryers, and paper towel dispensers for touch-free activation.
* Object Detection & Counting: Used in assembly lines, vending machines, and security gates to detect the passage or presence of objects.
* Gesture Recognition: Paired with a suitable photodiode, it can form part of a simple gesture-sensing system in consumer electronics.
* Industrial & Automation:
* Encoder Systems: Provides the infrared light source for incremental or absolute optical encoders in motors, robotics, and CNC machinery, offering high resolution and reliability.
* Barcode Scanners: Acts as the illumination source in high-speed linear and 2D barcode readers for retail, logistics, and inventory management.
### Industry Applications
* Consumer Electronics: Remote controls (for high-end, learning, or CEC-enabled systems requiring faster codes), data sync ports.
* Telecommunications: Optical isolators, short-haul data links.
* Industrial Automation: Optical sensors, safety curtains, machine vision lighting, encoder modules.
* Automotive: In-car data communication (e.g., older infotainment systems), rain/light sensors.
* Medical: Non-contact sensing in diagnostic equipment, hygiene-focused device activation.
### Practical Advantages and Limitations
Advantages:
* High Switching Speed: Typical rise/fall times in the nanosecond range enable data rates suitable for fast IrDA and digital communication.
* High Radiant Intensity: The small chip size combined with a molded lens produces a high intensity beam, excellent for directed communication and sensing over distances of several meters.
* Reliability: Robust construction with high electrostatic discharge (ESD) tolerance (typically > 2 kV HBM).
* Wavelength: 875 nm peak wavelength is well-matched to the high sensitivity of silicon photodiodes and phototransistors.
* Package: Standard T-1¾ (5mm) package allows for easy integration and standard holder compatibility.
Limitations:
* Directionality: The lensed package creates a relatively narrow beam angle (~±17° typical), which requires more precise alignment compared to wide-angle emitters.
* Heat Dissipation: At high continuous forward currents, junction temperature management becomes critical to prevent performance degradation and ensure longevity. A heatsink or pulsed operation is often necessary
