Questions tagged [light-sensor]
A passive device that converts light photons into an electrical signal output. Examples include photodiodes and photo transistors.
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DIY circuit that envolves Dusk till dawn and Motion sensor components [closed]
We just bought our house and as the dark time becomes more and more frequent, I would like to install some outdoor lights that lights up when it gets darker but stays at 50% of power and when someone ...
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Connect multiple PPG sensor to developing board
I'm pretty new to this world, so I'm sorry if my question sounds stupid.
I want to work with multiple optical sensors to record PPG simultaneously.
In particular, I want to use the MAX86916 sensor:
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Simulating OPT101 in PSPICE for TI
I want to simulate the OPT101 in PSPICE. PSPICE for TI does have that component. But the problem is the module responds to visible light in practical application. How can I impinge light on the module ...
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Determine of the colour of laser
I am currently working on a project which requires the the circuit to perform specific task if a specific colour of laser is detected (something like a basic remote control). Is there a sensor or a ...
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Need theoretical understanding of basis of IR sensor design
Below is a cutout of the IR sensor part from a heart rate sensor schematic. I need to understand how this part has been designed, what is the basis of the choice of the two resistor values R1 and R2, ...
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Simple circuit analysis
I am trying to figure out what the output voltage (V1) of this circuit is. Is the photodiode in reverse bias in this case, which means the current is flowing in (opposite of what is shown here)? Is ...
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Communicate with light Sensor BH1750 via I2C using CH341A (directly, without other microcontroller)
How can I communicate with the light sensor BH1750 using the CH341A device (like in the photo). Is there a way to do it without an arduino or a Raspberry Pi, just via I2C communication ?
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Can I use a TRIAC as an AC switch and an LDR as a switch controller to turn on and off a LED bulb?
I want to use a TRIAC as a switch for an AC light bulb and turn on the bulb when it gets dark and turn it off when it gets light using an LDR.
I want to fully cut off the bulb below a certain ...
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FT232 UART connected with a light sensor BH1750
I want to read serial data by a python script from a light sensor. I have the light sensor BH1750 and a USB-TTL Chip (see image). I have no idea about electronic hardware. Could someone tell me how I ...
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Choosing the right LED IR and the photodiode for optical beam sensor
I need to design an optical beam sensor for about 15-20 cm of distance - any obstacle between an emitter and a detector would trigger an interrupt for a microcontroller.
I was thinking about using a ...
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Pulse sensor issues and How to get -5V from Arduino
So I'm trying to make a pulse sensor using TCRT5000 IR sensor and arduino UNO (giving out 4.8V really from 5V pin) (Baud Rate 19200), and I'm supposed to get a pulse plot like this
But I'm getting it ...
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Feasibility of high-speed omnidirectional communication through infrared light
I am currently working on the design of a low-cost communication system based on IR LEDs and photodiodes for my research project. The goal is to transmit data with ~100ns pulses across ~0.5m distance (...
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Low intensity UV light detector
I wanted to build low light UV detector, I mean the measurement of light with wavelength 405 nm. I found two schemes:
First circuit:
And the second circuit:
I wanted to use operational amplifier ...
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DC transimpedance amplifier feedback capacitor
I am designing a simple photodiode light sensor circuit. The circuit will use a transimpedance amplifier to generate a usable voltage from the light level detected by the photodiode. The most basic ...
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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 ...
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Measuring ambient light intensity using BPW34 photodiode and TLC271ACP opamp
I've composed a schematic for measuring ambient light intensity using a BPW34 photo diode (Osram brand) and a TLC271ACP opamp. The output will be read using an ADC entrance of an MCU, so VDD = 5V here....
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I'm looking for a very sensitive photodiode [closed]
I'm working with a custom board that has a simple input to detect a closed switch, and I'm hoping to use it as a light sensor. I was thinking of just attaching a simple photodiode (Like this one: ...
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Light to Sound Device [closed]
I need a device that coverts blinking light to sound. What device would this be or called? Can this be done simply without soldering?
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How to calculate value of voltage by light intensity?
I want to write the code to turn the LED on when the light intensity that falls on the photoresistor decreases. So in daylight LED is off, and when it's getting dark LED goes on. I know that ...
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Help in identifying IC
I'm trying to identify the 16 pin white IC shown in the picture but I couldn't find any IC with marking code similar to that. I'm not sure but the board which IC is assembled on may be related to a ...
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LED luminosity decreasing over time
I'm measuring an LED with a light sensor but I'm running into a problem where the LED's luminosity (lux) is decreasing over time. Confusing since this is a simple setup, I don't know if the LED's I'm ...
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What is a modulated optical sensor?
I was told to try out a modulated optical sensor as a better and more "robust" option than the usual (unmodulated) optical sensors, saying the modulated ones are less subject to interference....
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Convert flame sensor ADC value to wavelength
I am working on a fire detector project using a flame sensor.
This sensor can detect IR light wavelength from 760-1100 nm using a YG1006 phototransistor.
I have read that if the wavelength is bigger ...
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ATMega2561 - How to connect this ambient light sensor using 1-Wire?
I am trying to connect the following components to an AVR ATMega2561:
1-Wire Master Interface DS2484 datasheet here
RGB Ambient Light Sensor APDS-9250 datasheet here
I have already managed to ...
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How to manipulate a PIR sensor?
The passive infrared (PIR) motion sensor detects movement of infrared light sources with wavelengths ranging from 7 μm to 14 μm. Is there a way to make it detect below 10μm or to make it detect ...
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opamp dc comparator [closed]
simulate this circuit – Schematic created using CircuitLab
I am trying to compare the voltages of the inverting and non-inverting terminal but no matter what input I put in, the voltages seem to ...
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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 ...
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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 ...
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Light control switch protection
first post here so be kind :)
disclaimer : I am not a professional and nor I have any engineering background, all this is part of a hobby.
After fiddling for months with SonOff / Tasmota / MQTT / Home ...
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LED not outputting square wave signal
I'm working on a sensor similar to an oximeter that measures light attenuation through a medium. I have an LED on one side, and an IC photodiode with on-chip transimpedance amplifier (OPT101) on the ...
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Optical pulse sensor not producing a clean TTL pulse
I have two of these optical pulse sensors monitoring LEDs on my electric and solar meters - Optical Pulse Sensor - Github
The first sensor outputs nice TTL pulses at 5V, the second sensor outputs ...
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APDS-9253 reads all data registers as 0
I'm trying to read data from an APDS-9253 with an xmega.
My i2c bus is working because I'm reading other devices without any problem.
From the datasheet it seems at power-up the sensor is not ...
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Can we program our smartphone camera to detect the frequency and time period of IR light?
My use case is this: I am emitting morse code using a sole IR light source, and I intend to detect the frequency and the time period of the light source using my smartphone camera. Can this be done?
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Simulating Photodiode sensor in LTspice
I am designing a current source that is going to control LED. With help of the DAC and microcontroller, I generate a voltage that goes to OP-amplifier, and afterward, I am opening my NMOS transistor. ...
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Retrieving energy data from dali2 D4i memory bank (202) of a luminare
I'm trying to read the memory bank202 from a DALI-2 supported led luminary for energy consumption.
it returns a value of zero. when i gone through the Dali part 252 energy reporting Doc. It asked me ...
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Meaning of two ADC channels in an LTR-559ALS-01 optical sensor
I am using an LTR-559ALS-01 optical sensor to read the level of ambient light. Everything works, but from the datasheet I can't make out why there are two analog channels for said reading.
Both ...
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Can a solar cell based lux meter produce useful readings for ultraviolet light?
I was reading the question Safety Guidelines for Ultraviolet LEDs? about ultraviolet exposure, and realized that a solar cell can probably detect this, since solar cells can also detect visible light, ...
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Light Sensor INT Pin function
I have a Light Sensor IC.
There is an Interrupt pin. I can see the status of it on page 9.
What is the high and low threshold exceed that they are mentioning in that table? Can someone tell me what ...
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Interpolation method for downsampling smartphone sensor data
I have a dataset containing lot of sensor measurements on Android smartphones, namely accelerometer, gyroscope and light sensor. The light sensor was sampled at a rate of 4 Hz and the accelerometer ...
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I'm making a simple dark sensor project with a light dependent resistor (LDR) and I want to replace the LED with a buzzer but it doesn't work
I replaced the resistors with small ones to give the buzzer more current,but itstill doesn't work. I checked my buzzer and it's working fine. The circuit works perfecly with the LED in the breadboard ...
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Software I2C and VL6180
Hell,
I'm trying to use the following sensor VL6180 with software I2C on PIC18F2458 running at 4Mhz, with USB functionality.
Currently the sensor doesn't work in terms of sending measurmenet, it can ...
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Live plant as a touch switch
I’m a Jack of all trades sort of guy but have basically zero electrical knowledge..
That being said.. I want to use a live.. real plant...to turn on and off a light. I tried a touch switch replacement ...
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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 ...
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555 darkness latch timer
I found a circuit to do what I thought I wanted it to do. I want an LED to turn on for a few seconds when an LDR detects darkness. The circuit works perfectly but now, of course, if the light source ...
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Which optical sensor to detect polypropylene wipes pass by?
Which sensor should I use to detect that a polypropylene sheet (light
shines through) has moved past a certain point? Would be nice if
it could easily connect to an Arduino.
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Why does CNY70 output peak at a distance only?
I am using the CNY70 sensor similar as in Understanding the CNY70 Reflective Optical Sensor (FTR: V=3.3V (instead of 5V) R=1k (instead of 200Ω) and X=10k putting the output voltage in the range of 0–0....
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Why aren't garage door sensors retroflective on one end?
Seems like they should be a transceiver + retroreflector, not transmitter + receiver pair. Is there a cost or safety reason for this?
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Reflective optical sensor
I am working on a project that uses a TCRT5000 reflective optical sensor.
Sensor datasheet is here
I tested this sensor in a room, the voltage at the output pin is high it is above 2.5V. While ...
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Converting the 0-10V output of a PMT to a +- 10V dynamic range
I am trying to convert the output of a photomultiplier tube module (Hamamatsu HC120) which ranges from 0 to 10V to +-10V in order to fit the full dynamic range of a ADC (MCC USB-205). To do so, I've ...
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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 ...
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