All Questions
Tagged with light light-sensor
24 questions
0
votes
1
answer
98
views
Why does TCS3200 lose accuracy when the light source is too bright?
I have a custom proof-of-concept project to detect fluid color within a PVC tube coming out of a patient's brain and turbidity (a reduction in light passing through) using an Arduino micro, a TCS3200 ...
1
vote
0
answers
96
views
Can I use a handheld spectrophotometer to calibrate my TCS3200-based fluid color assessment system?
I'm trying to build a system that measures color and turbidity within the tube that exits a patient's brain. Using a TCS3200 sensor and an Arduino micro, and a custom-made housing to ensure a dark ...
0
votes
1
answer
65
views
What component is missing?
I have an address sign that is supposed to light when it gets dark outside. The issue is the photodiode (assume that's what the part is) is broken and has broken off the board. I have tried connecting ...
3
votes
1
answer
136
views
Light reading diode?
I’m trying to think of a device to measure amount of UVA & UVB daylight for plants in my shed and so trying to work out what I could use to measure:
The amount of light
Its type
Its time
Be able ...
- 31
0
votes
2
answers
172
views
How good are Time-Of-Fligt (light) sensors for measuring small objects?
I found this sensor VCNL4040 and it has the emitter angle and the sensor angle.
Question:
How good is a Time-Of-Flight (light) sensor to measure small objects that are 100mm away and about 20x20mm in ...
- 1,388
0
votes
1
answer
51
views
How wide is IR-led light from VCNL4040?
I have an issue to solve. I'm going to measure an object that looks like this.
My question is if the sensor VCNL4040 have a very wide spread light or very "laser-like" light that ...
- 1,388
0
votes
4
answers
446
views
Light sensor detecting when the lights turns on AND when the light turns off
I would like to create a circuit using photodiode that detects when the lights turn on AND when the lights turn off.
The output should look something like that:
I want to create the simplest possible ...
- 3
2
votes
3
answers
1k
views
Can light damage a monitor/screen
I was reading some posts about how light can damage a camera by heating it up its internal components?
Link: Can camera sensors be damaged by light?
If I shine a 150-lumen flashlight at a monitor or ...
- 21
1
vote
1
answer
450
views
Best sensor to measure light intensity in open room
I am working on a project to understand how robot localization is effected by light levels. I am wanting to build a circuit which can be mounted on a small robot near the camera and can determine lux ...
- 59
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 ...
0
votes
1
answer
857
views
How to filter out certain wavelengths of light [closed]
I am trying to filter out certain wavelengths of light and I was wondering if there is a way that you can filter them out. I am using Silicon Photomultipliers (Linked below) and I only want to detect ...
- 113
2
votes
2
answers
516
views
Light sensors sensitive enough to detect for PWM from CF and LEDs?
I have an extreme sensitivity to PWM light sources such as computer screens and light bulbs. This can make it very challenging to make a purchase as I end up having to do lots of guesswork with ...
- 2,955
0
votes
3
answers
549
views
dc voltage control for LED lights?
I'm looking for a little bit of help on a project I'm working on.
I need to find some way to make led light bars (18w and 120w) to automatically start out dim and gradually brighten to full ...
- 1
-1
votes
1
answer
2k
views
Which one is better to build lux meter, either LDR or photodiode?
I want to add the lux meter to my application. My controller works with 3.3V and ADC max reading voltage is 1.2Vref.
I tried with LDR but I'm not able to get accurate values and the values also not ...
- 21
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
3
votes
3
answers
730
views
Using multiple white LEDs to obtain a unique CCT
I need to swipe between two white shades from one to another color temperature, let's say from 2700K to 6000K. Can it be done by simply mixing the intensities of two LEDs of respectively 2700 and ...
- 1,305
0
votes
5
answers
2k
views
What's causing a bad response time of a phototransistor at 100 Hz
I am working on a project that involves communicating with LEDs. I need to be able to detect the state of a light source that is flashing at about 100 Hz. I am using the phototransistor that comes ...
- 131
0
votes
1
answer
290
views
BH1750 Sensor ICs - Block Diagram - Why it has capacitor connect output to input of OpAmp?
The image from BH1750FVI datasheet. http://rohmfs.rohm.com/en/products/databook/datasheet/ic/sensor/light/bh1750fvi-e.pdf (page 4)
I don't know why it has the capacitor connect output and input of ...
- 1
-3
votes
1
answer
122
views
How do I build a Circut to create temperature changes in LEDs? Looking for a range of 3000 to 6,000 for photography? [closed]
I see commercial lights for photography that can change color in the range of 3-6,000 or tungsten to daylight values. These are not arrays of three RGB lights but rather single LEDs and the ...
- 122
0
votes
2
answers
2k
views
Sensing directional light
I am looking to detect the amount of light coming from a specific direction that lands in a specific area on a PCB. In my research, I have only found ambient light sensors and never any kind of ...
0
votes
1
answer
570
views
Light Detector/Identifier circuit using photodiodes
I'm currently completing my final year project and am currently stuck going round in circles as how to complete it.
To summarise: I need to design a circuit which is capable of IDENTIFYING a light ...
- 1
1
vote
1
answer
584
views
Is Deuterium arc lamp a AC or DC light source?
I have created a prototype photo-detector circuit to use in spectroscopy. The micro-controller code take 120 A/D readings and then returns average.
I have noticed that when I use visible light (normal ...
- 425
2
votes
4
answers
254
views
How can I sense if a cane is being held upright or fallen down?
I am trying to make a little wireless-connected gizmo to attach to my grandfather's walking cane. The idea is that when it senses the cane has fallen down, it would alert/call one of us so that we can ...
- 4,972
4
votes
2
answers
1k
views
Are photoresistors reliable for light sensing applications?
I've used photoresistors for hobby projects before, such as this one:
http://www.foxytronics.com/learn/electronics/kit-guides/starter-electronics-kit-guide/making-an-led-light-sensor
However, now I'...
- 4,576