Light is a tag about anything generates photons in the visible spectrum

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1answer
28 views

Controlling lights powered via mains using an 8 channel relay module

I've come up with this schematic and I'm just wondering if this is correct. I'm using raspberry Pi GPIO pins to blink 240V 40W light bulbs using a relay module. Ignore mains for the Pi for now I ...
25
votes
5answers
13k views

Why are Edison screws allowed to be used? [on hold]

Why are the Edison screws allowed to be used? They seem unsafe. Why are they designed that way? They require a complete grounding system to ground devices for the rare situation where the hot wires ...
2
votes
3answers
56 views

Sensor to rapidly sample light intensity of a small area at a distance?

I'm looking for a sensor or method of rapidly sensing light intensity of a 1-inch x 1-inch square of a LCD monitor at a distance of 1-1.5 feet away. Does anyone know if such a thing exists, or has ...
1
vote
1answer
60 views

Decreasing lumen and power usage

I have bought four of the very same led light bulbs two weeks ago. Their lightning characteristics appeared to be the same (brightness, angle, color). Two days ago I have realized that one of the ...
0
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1answer
66 views

Can you explain how the following garden solar light circuit works?

I found the following circuit in a solar garden light. The cut off white and black wires are from the solar panel. What does the 4 pin transistor do?
1
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3answers
119 views

Create a circuit with 3 identical light bulbs that all have different brightnesses

I'm learning about circuits in my physics class, and we've been given an assignment to create a circuit that can only use 3 identical light bulbs that should all have a different brightness. I've ...
0
votes
2answers
91 views

Would the frequency of LED be equal to that of microcontroller

Suppose I have a simple LED driving circuit i.e. an LED and a resistor in series which is driven by a pin of a microcontroller. Now I set the frequency of this pin to say 1Khz, will the LED flash with ...
0
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4answers
84 views

Audio transformer for 12V light emitting circuit

I'm working on transmitting audio through light using amplitude modulation of an LED, received by a solar panel connected directly to an active speaker. Something like this: simulate this ...
1
vote
1answer
68 views

Non-led simple bicycle dynamo light system

There have already been questions about how to build a bike power supply based on the bikes dynamo. Most of the answers contained lots of basic components. Some answers here are making a full wave ...
0
votes
0answers
42 views

What kind of sensor i should use to detect object that blocked the light?

i want to ask about the sensor i should use for this problem. My problem is i want to detect if there something blocked the light. Im also ignore light from environment, so consider there's no light ...
-3
votes
1answer
102 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 ...
4
votes
3answers
246 views

P-channel MOSFET as high-side switch gets hot

So I'm trying to control my front lights of my car using an Arduino Nano. In total there are 14 lights (including foglights and blinkers etc.). I'm using two 75HC595 shift registers to control these ...
0
votes
2answers
30 views

Ground wire in custom capacitance-dimmable metal lighting fixture

I'm wanting to design my own lighting fixtures, both for cost effectiveness as well as the design appeal (inspired by a particular designer's lighting fixtures) that uses a wooden base with metal ...
0
votes
1answer
81 views

Automatic Temperature Controller with Thermistor (Incandescent BULB)

I'm new in this site And sorry for my english language.. I need a circuit for my little oven. I use an incandescent bulb (4x100W) for heating, and I want make a dimmer circuit to change output using ...
0
votes
1answer
139 views

Is there a digital input that registers light? / Can only ADC pins register signals from an LDR?

I have been building a traffic light over the past year as a GCSE project. Initially, what was unique about it was that, the pedestrian interface would light up when it was dark outside. Subsequently, ...
0
votes
2answers
44 views

What is a suitable material to cover photo voltaic panels?

I'm building a small, portable, modular solar panel array to charge 5V power banks, phones, etc. I got most of the electronics down, the Step-Up converter, by-pass diodes, blocking diodes, as well as ...
4
votes
3answers
120 views

repeatedly turning an incandescent light bulb on and off every 20 seconds will cause damage to the bulb?

I have seen similar questions to this one but none of them were asked in the range of seconds only minutes. I just finished building a incubator for chicken eggs and I am using an incandescent light ...
4
votes
2answers
591 views

What does the circuit look like to switch two lights using two switches into four different states?

At my workplace there's a room with two entrances, each featuring a push button light switch, A and B. There are two ceiling mounted lights, 1 and 2. Switch A switches both lights on/off. Funny ...
2
votes
2answers
544 views

If I flick the light switch on and off will it damage the light?

Ive heard that when you flick the light switch on and off repeatedly it damages the bulb. I know this is certainly not true for LED bulbs, but Im wondering if and how it damages other kinds of bulbs....
0
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2answers
196 views

Bulb replacement in a car 12V 60mA vs 14V 65mA

The climate control in my car needs to have some backing lighting bulbs replaced. Can I use a 14V 65mA bulb instead of the 12V 60mA bulb that is suggested by other people who have replaced these ...
0
votes
2answers
107 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
1answer
34 views

Creating a Strip of Light Using LEDs

I am looking into creating an illuminated string of leds where the individual LEDs are not visible, but that a shape is illuminated. The shape would be a various sized rings the biggest being about ...
0
votes
1answer
97 views

SSR not switching dimmed load

I have a system where there is a "master dimmer" (an 800W dimmer designed for household lighting). From that master dimmer, I have a few SSRs switching 40W incandescent light bulbs. The idea being ...
0
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1answer
70 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 ...
0
votes
2answers
118 views

Why would an electronic timer have a minimum load?

I need to replace an electronic timer lightswitch, and both the old one, and this example of a replacement, state that they have a minimum load of 40w. Why would the switch have a minimum load, and ...
-2
votes
2answers
70 views

How bright are the dimmest LEDs and what's their typical usage? [closed]

High power extremely bright LEDs are more and more popular in various lighting applications. What about extremely dim low power LEDs? How bright are those and how are they typically used?
2
votes
4answers
564 views

Controlling AC light bulb intensity

I saw in some movies that indoor light intensity is controlled with human presence and distance from the sensor (the lower the distance, the higher is the light intensity). I am very interested to ...
0
votes
1answer
86 views

Wiring a lamp in [closed]

Hi guys I'm very new to electronic wiring so take it easy on me. I have a drone that I'm trying to connect a little 12v floodlight too so that it can see at night when it flys; the problem I'm having ...
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votes
1answer
144 views

How to measure voltage of a track lighting fixture?

My house has track lighting that takes MR16 halogen bulbs. I would like to measure the voltage being put out by the fixture using a multimeter. I removed one bulb, set my multimeter to V-DC and ...
18
votes
3answers
2k views

Why are there only RGB and RGBW-LEDs, but none with more chips inside one housing?

In another thread the question emerged, where the LEDs with 5 or more dies of different colours are. (Kudos to Brian Drummond) The background is as follows: RGB LEDs are very popular for creating ...
-2
votes
4answers
181 views

Can I use an ethernet module (or an USB connection) for light communication? [closed]

I'd like to transmit data (e.g. copy a file between two computers) at high speed via light. I found lots of examples around the web but mostly the speed is really slow because a serial connection (...
1
vote
2answers
204 views

Am I having a power supply issue with my LED lights strips in series, or have I done somethine else wrong?

I bought two LED light strips and connected them together end-to-end using a solderless snap connect. The strips are each 5 meters long, "LEDMO SMD 2835 White Non-waterproof LED Light Strip - DC12V ...
0
votes
2answers
125 views

solar panel: how much energy has been charged?

first time here and still learning. I have just ordered a 100W solar panel with these specs: V:21.61V I:5.73A I am aware that to calculate the power output i can multiply V x I. However the ...
3
votes
1answer
54 views

Solid-state lighting [closed]

Background Consider the following technologies: 100 lm/W OLED (2008, source) 303 lm/W LED (2014, source) 94 lm/W LEP (2015, source) For growing food, the preferred measurement is ...
0
votes
1answer
29 views

~12VDC+ Automatic Dimmer Switches

Most automotive vehicles typically have their interior lights fade out 30 seconds or so after the doors are closed. The way I understand it, closing the door will usually depress a momentary on/off ...
5
votes
2answers
146 views

Electrically switching between horizontal and vertical light polarization

I would like to be able to electrically switch between horizontal and vertical light polarization. This polarization filter is supposed to be portable attachment running on a battery in front of a ...
0
votes
1answer
112 views

Amount of light by an LED

I am supposed to use an light having the following specs. as described in the below statement. "A red light, equivalent in its luminescence to a 21 W light bulb is to be used." On an average how ...
0
votes
4answers
136 views

Light effiency or efficacy and watt to heat output

I am on a light forum and there are debates about watt heat output of lights. I'm using my common sense for the debate but can't find the data online to support my ideas. People are thinking that ...
1
vote
1answer
553 views

Why are “flicker flame bulbs” always bulbs or how do flicker flame bulbs work? [closed]

In other words, I've never seen the type of filament (if filament is the correct term—if not, what is the correct term?) outside of a bulb—as seen in the video linked to below. Is there something ...
2
votes
2answers
96 views

Electric light bulb burns out

Why electric light bulb more often burns out when we switch from OFF to ON our wall switch, but not during regular work? What happens to it so it burns?
1
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0answers
69 views

Idea for a modern LightGun, would it be possible?

Old lightguns used CRT monitors to work, and are not compatible with modern systems anymore. I've com up with an idea and would like to know if it's doable and what problems there could be. The idea ...
0
votes
2answers
88 views

How to use Lightsensor relay with 3v output

I want to find solution for one small circuit with Light sensor. I need one small light sensor to drive 3v output. The power of all the circuit must be 5v and when the light sensor is off (no light)...
0
votes
2answers
113 views

Does air flowing over a bulb affect the amount of lumens produced? [closed]

If a bulb is cooled by air flowing over it, would that change the way light is emitted? I see contradicting evidence that air cooling bulbs changes how much light is emitted because the cooler air ...
2
votes
5answers
479 views

Flash a light in a specific pattern

It is quite easy to flash a light in say, 0.5 seconds on, 0.5 seconds off. But what if I wanted to flash it say 0.5 on, 0.5 off, 1.0 on, 0.5 off? Are there any IC's that would allow that?
1
vote
2answers
89 views

What kind of micro bulb is this? [closed]

I am doing a clone of my Honda's dashboard circuit. Everything is fine except I cannot find the tiny backlight bulbs (see photo) that are used for the dashboard button illumination. Are they standard ...
5
votes
3answers
1k views

Why/when would you use a light to frequency converter?

I have looked at the TSL235 light to frequency converter and for measuring ambient light it seems expensive (~$1.50). What application would you have for using a light to frequency converter vs a ...
0
votes
1answer
195 views

Illuminating the wall of a transparent tube

I have a plastic tube that has a wall thickness of around 3 to 4 mm and it is transparent. I am trying to build a ring for the top of the cylinder that just illuminates the sides of the tube, but ...
0
votes
1answer
178 views

Reduce RF noise from a DC inverter

I have got this strip of EL light. I am using it in a project where I am also using 2.4g and 5.8g band of RF. The DC inverter creates a lot of RF noise (understandably) as it's inverting from DC 12v. ...
0
votes
2answers
446 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 ...
11
votes
3answers
1k views

Why does the intensity of light in LEDs not increase with current after a particular value?

I read in books that light intensity from an LED does not increase beyond a certain value of current. The amount of light emitted depends on the combination of holes and electrons. If so, then as the ...