Smart phone apertures shrink from sensors by up to 50%

New proximity sensing and proximity/ambient light sensing modules which enable android smartphone manufacturers to reduce the sensor aperture in the display’s cover glass to its smallest diameter have been introduced by ams.

Use of the TMD2620 proximity sensor or the TMD2725 combined proximity and ambient light sensor enables manufacturers to reduce the aperture’s size by as much as 50%, improving aesthetic appeal, especially in devices with a white or light-colored bezel. The TMD2620 and TMD2725 enable aperture size as small as 1.4 and 2.0mm, respectively.

The TMD2620 and TMD2725 feature a breakthrough in optical module packaging which allows the emitter – an InfraRed Emitting Diode (IRED) – and photodiode to be placed just 1.0mm apart. Lenses on top of the emitter and sensor along with an optical barrier between them help to minimize crosstalk, caused by reflections from the surfaces of the cover glass. Offset adjustment registers eliminate the effect of any residual crosstalk from the module’s proximity calculations. Automatic ambient light subtraction further enhances the accuracy of the device’s proximity measurements. The ability to measure up to a range of 100mm is comparable to laser-based solutions.

Herbert Truppe, Senior Marketing Manager ams, commented: “Until now, inability to overcome the effects of optical crosstalk have prevented android phone manufacturers from reducing proximity sensing apertures below 3.0mm. Now the TMD2620 and TMD2725 overcome those challenges and enable a smaller aperture than has previously been possible.”

The TMD2620 and TMD2725 are in volume production now. Unit pricing is $0.36 for the TMD2620 and $0.43 for the TMD2725, both in 1,000 unit quantities.