All Questions
15 questions
2
votes
0
answers
140
views
IR LED Safety: Where does this OSRAM App note (AN090) formula come from?
The formula is from OSRAM application note AN090 "Eye safety of IREDs used in lamp applications":
$$ L_{ir} \approx \frac{I_e R(\lambda)}{Z^2} $$
In the app note, they don't give a reference ...
- 31
3
votes
1
answer
205
views
How to replace TCRT5000 IR sensor with TCRT1000 IR sensor
I've got a pulse sensing circuit based on the TCRT5000 IR sensor. Its working fine and I can easily see the pulse when finger is placed. But I tried replacing it with the TCRT1000 but there is ...
user323019
1
vote
2
answers
164
views
IR LED Safety: Subtend Angle and Retinal Exposure Limit
The relevant formulas from OSRAM AN090 "Eye safety of IREDs used in lamp applications" with slight modifications :
$$ Z = (l + w)/2 $$
$$ \alpha = Z/d $$
$$ L_{ir} \approx \frac{I_e R(\...
- 31
0
votes
1
answer
162
views
Photo Diode Receiver
I have designed a 5KHz Photo Diode Receiver circuit that Consists of a number of blocks. first stage of this circuit is a TIA.
I have problem with DC IR Light (Like SUN Light), when sun light shine on ...
2
votes
2
answers
399
views
Burn hazard of IR LED Array Question
I am performing eye safety calculations on a device and I have hit a roadblock.
To perform the calculations I have been following the IEC 62471 "Photobiological safety of lamps and lamp systems&...
- 53
1
vote
2
answers
191
views
Is there a way to measure or infer the color of a material from a distance (~2m), without using visible light?
I've recently started working on a graphics/SLAM project. We've encountered a problem that requires us to measure or infer the color / spectral reflectance (and ideally albedo) of points on objects in ...
2
votes
1
answer
176
views
Circuit topology name and function for PNP transistor in light barrier circuit
I have seen this rather simple circuit for end position detection of a DC motor drive mechanism. An infrared LED (V402) and a phototransistor (V401) are used as a light barrier.
Can someone give me a ...
- 7,803
0
votes
0
answers
49
views
Light illumination method for video camera and CV detection
My control application implements human face detection and recognition with using of CV library. My device uses usual VGA USB video camera.
Problem:
Good and uniform light illumination allows ...
- 13
0
votes
1
answer
40
views
Infrared diodes illuminator scope
Can anyone tell me if there are certain specific criteria that states whether an infrared led can be used as an illuminator particularly the ones they use on hunting scopes.
Would a tsal6100 for ...
- 81
0
votes
2
answers
195
views
How to measure body temprature and HBR with just one IR transmitter and receiver
I want to measure body temperature and heartbeat rate only with a IR receiver and transmitter. How could I do that? Is it an accurate method? Or I have to use IR temperature sensor for this.
- 222
38
votes
10
answers
50k
views
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 ...
- 483
2
votes
2
answers
3k
views
Infrared LED vs halogen light output comparison
I am thinking of using a high power ~50W IR led. I am wondering if LED IR is more efficient than halogen as is the case with visible light LED's? I couldn't find the light output of either IR halogen ...
- 739
0
votes
2
answers
2k
views
TSOP382838 IR receiver keeps outputting signal even if no infrared light is present [closed]
This is a beginner question.
This is my first time using an ir receiver. The one I have is a TSOP38238. I have setup a simple circuit that consists of a visible led and receiver. When I have no ...
7
votes
2
answers
5k
views
What are the relevant parameters for a reverse-biased LED light sensor?
Following this appnote (PDF) on using photodiodes, I'm connecting an IR LED as a light sensor and emitter, configured like this:
To emit light, I pull PIN1 high ...
- 7,749
3
votes
2
answers
362
views
Which infrared bulb should I use with a photodiode?
I'm currently using a photodiode (found here) along with the appropriate emitter to send data between mobile robots. I'd like to the sensor to optionally be used as an ambient light sensor using a ...
- 641