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I am designing a device that uses a remote control with an infrared emitter and receiver. Originally I designed the device with a Tsop38238 but this sensor seems like it's better suited for a DVD player. You have to aim the remote directly at the sensor to get it to work and it only works in one direction, the front of the sensor. This doesn't really work with my design which is actually a bike alarm.

Are there inexpensive IR sensors that receive signals from any direction around it? What keywords should I search and what specs should I look for? By the way, I would like my center band frequency to be 38 kHz.

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    \$\begingroup\$ Welcome to EE.SE but please note that direct shopping questions will result in fairly prompt closure of your question as per site rules. You might want to edit out the request for part recommendations. \$\endgroup\$
    – Transistor
    May 1, 2021 at 9:02
  • \$\begingroup\$ I’m not aware of any sensors that have that delude a field, but you could consider 6 sensors on the sides of a cube or 4 on a tetrahedron, depending on the angles at which the devices are acceptably sensitive. \$\endgroup\$
    – Frog
    May 1, 2021 at 9:19
  • \$\begingroup\$ Got it. No part recommendation but specs and what type i should look for please. 😁 \$\endgroup\$ May 1, 2021 at 9:19
  • \$\begingroup\$ is this supposed to work outdoors? \$\endgroup\$ May 1, 2021 at 10:36
  • \$\begingroup\$ It is not understandable from your posting you need sensor or IR receiver. There a lot of special IC for receivers, they are sensitive enough and can receive reflected signal. \$\endgroup\$
    – user263983
    May 1, 2021 at 11:26

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You need multiple sensors anyways because with one sensor its going to be staring right at the sun. With multiple sensors you can at least ignore the ones staring at the sun.

Photodiodes and phototransistors in flat SMD packages have the widest field of view: 60 degrees half-angle half-max sensitivity but its a sinusoid covering +/-90 degrees at 0 sensitivity at the edges.

I also really doubt you actually need EVER direction. I imagine horizontally outward in every direction would be sufficient. The very wide field of view in the types of devices mentioned above might actually cause you problems by having the sun in their field of view even if pointed horizontally.

I would go with narrower in which case you would need to look at through-hole photodiode and phototransistors. The ones that look shaped like LEDs have conical fields of view so for horizontally outward but not upward looking you need multiple narrower field ones in a ring. There are radial side mount packaging which have a wider horizontal field of view than vertical which would help them ignore the sun if it is to your back.

You also want the black opaque, visible blind packaging.

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  • \$\begingroup\$ Multiple sensors not strictly needed if you have a well-implemented light pipe or capture lens. tlfong01's answer of course provides a cautionary example of what not to do: if you use lensing, the material needs to be appropriate for your wavelength. \$\endgroup\$
    – Reinderien
    May 1, 2021 at 17:14
  • \$\begingroup\$ Okay so you are saying more than one sensor arranged in a ring and if it is in flat smd package, that will increase field of view. \$\endgroup\$ May 1, 2021 at 21:46
  • \$\begingroup\$ @user3308807 Yes. A flat SMD package has the widest field of view. The smallest number you can use is 3 SMDs which will give you at least 50% sensitivity from any horizontal direction. as long as you are within +/-60 degrees vertically \$\endgroup\$
    – DKNguyen
    May 1, 2021 at 23:22
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Answer


lidar


You can try putting a "all direction (Fresnel Lens) " cap on your IR receiver, but not sure it works on a transmitter. Perhaps you can rotate the transmitter regularly, using a servo or stepping motor, like the LiDAR car. Ref 6.


pir


References

(1) PIR Motion Sensor Module

(2) PIR (motion) sensor product sheet US$10 - AdaFruit

(3) PIR (motion) sensor tutorial - AdaFruit

(4) Fresnel lens - Wikipedia

(5) Rpi3 LIRC Library and UART IR Transceiver Setup Problem - Asked 2019sep11 Viewed 4k times

(6) Controlling 5 LIDARs using Raspberry Pi - Rpi SE 2019sep09


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    \$\begingroup\$ Are you sure a lens intended for PIR (far infrared, ~10 micron) will work well with the near IR (~1 micron) light coming from a remote control. \$\endgroup\$
    – StarCat
    May 1, 2021 at 9:42
  • \$\begingroup\$ Ah, only 5% sure. raspberrypi.stackexchange.com/questions/103452/…. Or the OP can rotate both the transmitter and receiver. \$\endgroup\$
    – tlfong01
    May 1, 2021 at 9:49
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    \$\begingroup\$ No, this is the wrong kind of IR. The OP needs near-IR for communication, not long IR for detecting movement. Materials that are transparent to long IR can be opaque to short IR and I am pretty sure that polyethylene is in that category. \$\endgroup\$ May 1, 2021 at 11:41
  • \$\begingroup\$ Thank you for pointing that. I thought 38kHz is the usual remote for TV set. I have never heard of polyethylene.I need to google and try again. Cheers. \$\endgroup\$
    – tlfong01
    May 1, 2021 at 12:33

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