Proximity Sensing 

ams OSRAM offers digital proximity sensing modules and a complete portfolio of emitters, photodiodes and analog front end ICs to enable high performance custom proximity sensing solutions. 

Proximity sensing using reflected light intensity 

Simple presence and range detection can be achieved using an adjacent light source and photodetector. The intensity of the light reflected from the source is inversely proportional to the distance of the target. 

Simple proximity sensors implement a threshold on reflected light level, indicating whether there is an object in close proximity or not. Relative measurements of distance are also possible, although require a high degree of scene consistency and calibration, because the absolute reflected signal level also depends upon the angles, target size and reflectance. Whilst most applications are for very short distance, implementations with over 1m range are possible. 

Applications for intensity proximity sensors include: 

  • User detection: Mobile display switched off when phone is placed to ear; Wireless earbuds turn off when not in ear. 
  • Force touch sensing, by detection of the displacement of a touch panel surface 
  • Gesture sensing 
  • Industrial automation  

Digital Proximity Modules 

ams OSRAM offers complete digital proximity sensor modules, which integrate VCSEL driver, VCSEL photodetector, analog front end, pulse/detector sequencing digitization, and readout over I2C. Designed for detecting the user in mobile and wearable devices, these devices offer minimum size and power.  For example: 

  • TMD2636 (pictured) integrates a complete proximity system into a 2x1x0.35mm module, requiring just an aperture of just 1.5mm circular diameter or 1x2mm oval.  

We further offer combined function modules that integrate proximity, ambient light and color sensing, optimized for space and power constrained integration into mobile devices for display management. For example: 

  • TMD2712 integrates proximity and ambient light sensing into a 1x2x0.5mm module 
  • TMD3725 integrates proximity, ambient light, RGB color and IR sensing into a  2.0 x 3.65 x 1.0mm module 

Components for custom proximity sensors 

ams OSRAM offers a complete portfolio of emitters, detectors, and ICs to build custom proximity sensing solutions. These include: 

Infrared LEDs of all sizes and power levels at 850 and 940nm, including: 

  • Firefly series in tiny 0402 footprint packages 
  • TOPLED series in 3x3.4mm footprint packages 
  • OSLON P1616 series, delivering up to 1320mW in a compact 1.6x1.6mm footprint with emission angles of  ±35°, ±60°, ±65° and ±70°x±45°. 
  • OSLON Black series, delivering up to 2350mW in a  3.75 x 3.75 mm footprint with emissions angles of  ±25°, ±40°, ±75° 

Infrared VCSELs and VCSEL based illuminators 

Photodiodes that deliver high sensitivity, linearity and low package footprint. For example TOPLED SFH 2202 and CHIP LED SFH2705/6

Analog front end ICs which integrate an emitter driver, ADC, sequencing of emitter pulses with the receiver, signal processing and readout over I2C. Designed for high performance optical vital signs monitoring applications, the AS7057 and AS7058 ICs can also be used to realize high performance pulsed proximity sensing solutions.