Questions tagged [brightness]
Brightness is an attribute of visual perception
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How reliable using this LED under its rated specs?
I want to control the built in LED of this switch by an MCU GPIO pin which 3.3V. The datasheet of the switch is given here.
Since there is almost no detail but the "Voltage & Rating: 12V @ ...
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Is brightness for WS2812B LED voltage dependent?
I understand that this would be true for any other regular LED.
The doc states that it accepts +3.5~+5.3 V.
I was wondering if it is somehow internally converted to operate at the same level as long ...
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LCD Brightness Control & LCD Datasheet Interpretation
I'm working on a handheld gaming project using a LS020B1DD01 LCD panel and am looking for a way to control the LCD's brightness via two buttons. From my understanding, the backlight on this panel is ...
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Identify correct voltage/amperes from bulb brightness
Is there a method to establish correct voltage of an incandescent bulb by offering a voltage and measure brightness? In other words, is there a chart that tells you the brightness range of a 2.5V bulb ...
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Estimating apparent LED brightness: current or power?
TL;DR - based on the physics of LEDs, does current or power give a better estimation of actual light output of an LED?
I am building a dimmer circuit with a few discrete steps, to operate a COB LED ...
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About LED dimming using PWM
I have some questions about how it is possible to dim an LED using PWM. I saw some videos and explanations of how the duty cycle affects the brightness and some methods to effectively dim a LED with ...
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Safety regulations (USA) for high-power LED brightness (e.g. 1+ W)
For a "mostly" shielded sequence of 1 W where a user will see light bleed through small gaps in a device and (for argument's sake) might see a direct reflection of one of these 1 W LEDs (a ...
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7 segment LED displays
I notice the surface area of the decimal point in my 7 segment displays is only 1/4 of the ABCDEFG segments. Should I reduce the drive current accordingly, to achieve matched brightness? Can't find ...
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Efficiency of green High Power LED compared to efficient white
Whenever I see color High Power LEDs (for example green 3W on Star) I see disappointing efficiencies:
For 520 nm the theoretical efficiency is 683 lm/W * 0.88 (green) = 601 lm/W. But most are ...
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How to adjust both brightness and contrast of a TFT LCD display
I am developing an HMI using the display "S039QWQ01HS" and I have the requirement to provide control to adjust the brightness and contrast of it.
For the brightness control, I have already ...
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How to measure intensity (lumen) of a light source?
Let's say I have an x800 cree LED (which was supposed to be 4000lumen) and a cheap lux-meter (thinking of buying one like this).
My question is, which is the physical setup to measure the true ...
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LED resistor basic wiring [closed]
I am looking for a single bright LED light. I'm using:
a red 5 mm LED
a 5 V, 2.5 A AC adapter
a 1 Ω resistor
It works, but doesn't seem very bright.
Am I correct or completely wrong? What is the ...
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Globe brightness in series circuit
So in a simple DC series circuit, why do some globes shine more brightly than others? And which ones are the brightest? Obviously each consumes a certain amount of voltage but I don't think the ...
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How can I regulate brightness of a LED strip with a potentiometer
I have a 12V, 5m long LED strip and an adapter (12V 1A). I want to control the brightness of the LED strip with a potentiometer, I found a simple circuit that involves only a pot and IRFZ44N ...
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increase the maximum brightness for a laptop replacement screen [closed]
I would like to increment the maximum brightness for a laptop replacement screen such as this one
How difficult that could be? I haven't bought the screen yet so any hint about the type / model and ...
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