Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [infrared]

IR is electromagnetic radiation with longer wavelengths than those of visible light at 0.74 micrometres (µm) to 300 µm, which is extends the nominal red edge of the visible spectrum.

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Why do IR remotes influence AM radios?

When I put my IR remote near any AM radio and push any button on the remote, I can hear a sound from the radio speaker (like beeping). This phenomenon is very weird for me because the radio has no IR receiver inside. On the other hand, the frequency…
M.A.K
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If Infrared not visible, why the red LEDs?

If infrared light is not visible to the human eye, why do most tv remote controls and security cameras appear to have a visible red colored LED lit when the infrared light is being emitted? Is that visible red light present as a convenience…
dtmland
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Why are many IR receivers in metal cages?

I'm guessing it's a Faraday cage around the receiver, but don't know why they might need one. Is there some sort of common interference around 38kHz (their operating frequency)? It's the only component I think I've used that gets this special…
R Zach
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Why is the bitrate of infrared smaller than the bitrate of WiFi?

Infrared has a frequency of 300 GHz – 430 THz, while WiFi has a frequency of 2.4 GHz or 5 GHz. As the frequency of infrared is greater than the frequency of WiFi, the transfer rate (bitrate) of IR should be greater than WiFi. In reality, IR…
Muhammad Ikhwan Perwira
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Can I electronically trigger a PIR motion sensor?

I would like to trigger a PIR sensor using an infrared LED. Is that possible? My goal is to simulate motion in front of the PIR, when there otherwise is none. I tried using a handheld remote control, but that didn't seem to work.
user1574082
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Keeping those IR LEDs

For all the other stupid things I often do, I've found ways to boobytrap myself. For example keeping my wallet on the floor where the door opens - I can't help but stumble on it when I leave the house. But here's an electronics parts problem that…
DarenW
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Ideas to measure 2D position of an object constrained to X-Y plane

I am working on a project, and an aspect has come up where I would like to measure (track continuously) the X and Y position of an object across a 2D plane. The object is moved by a person, with the object's movement constrained to the 2D plane (so…
boardbite
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Sensor for detecting airsoft bullet

I'm trying to make airsoft chronograph/chronometer (a device that measures airsoft bullet speed). The idea is to measure time in which bullet is traveling from point A to point B, and then I can calculate bullet speed. Bullet is shot into plastic…
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How to make IR proximity detector immune to the daylight?

I am trying to make an infrared proximity measurement device. I want it to be in the range of 10cm or 4" (maybe 15 cm?). The frequency I use is 10 KHz. Here is the circuit I used, except that I have used 1 nF capacitors and resistors that suits them…
abdullah kahraman
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Dangers of IR LED

I would like to build a DIY laser tag system. The website milestag recommends a Vishay Tsal-6100 as IR-LED. Here is a datasheet: http://www.mouser.com/ds/2/427/tsal6100-279822.pdf Since I want to focus the light (maybe one or two degrees divergence…
lhk
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How to Use SFH235 IR Photodiode Correctly?

I have an SFH235 ir photo-diode (which datasheet can be found here) and only basic knowledge of electronics. I want to connect the photodiode to an Arduino (the grand-plan is to add an ir diode and build a distance sensor). I understand that…
Artium
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Will a 950 nm IR emitter work with a 870 nm phototransistor?

I'm planning to build a simple IR light barrier across a distance of 15 mm. I plan to use this receiver with this emitter. The reason is to have some SMD PNP capable components. The emitter and sensor have a slightly different IR wavelength. Will it…
Chris
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Help with or hints for decoding an IR protocol

Some time ago I bought a simple and cheap little IR-controlled toy helicopter (same as this one - it's called "Diamond Gyro" or "Diamond Force"). For fun, I've been looking into controlling it via an Arduino. Update: Got the protocol figured out;…
Flambino
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The LED is dead... Why?

I have one OSB4XNE3E1E IR LED datasheet I use a battery type Li-ion 18650 and it's 1200 mAh - 3.7 V. The maximum voltage of the battery is 4.2 V maybe "when full charged" and when I made the circuit it was not fully charged so it read 3.99 V. The…
Pcp115
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How do universal IR remote "codes" work?

It is easy to find this kind of reference when searching for IR protocols and codes for specific equipment. The actual IR transmission contains far more data than these small codes can hold. What exactly do these codes represent? How can four digits…
Filipe Nicoli
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