ultra bright led light bulbs Lumens and the Brightness of an LED Flashlight (Torch)

by:Leimove     2020-03-07

Do you remember the flashlight from the last few days?If you want a lot of bright light, the flashlight weighs a few pounds, and even then you may have that big black spot in the center of the beam.Either the area covered by the beam is so small that it is completely impractical for some use.With the development of LED bulbs, flashlight technology has also changed.The flashlight can now weigh just an ounce, providing a lot of light in a concentrated beam in the case of a large range or both.In the 1880 s, the invention of the first dry battery made flashlight technology possible.In 1897, David missell invented a flashlight made up of paper tubes, brass end caps, and cattle eyeballs.It runs on three D-type dry batteries.The officers who were passed on to the New York Police Department received positive feedback.Early flashlights generate 8 to 10 lumens per watt.Use incandescent lamps before LED technology.These glass bulbs are equipped with ar, Krypton or xenon in a vacuum or inside, and have tungsten wire to provide light.LED technology has greatly changed the flashlight.As these bulbs are more efficient, fewer batteries are needed for the lights needed for production.The size of these flashlights is reduced, and the total output of light is also increased.LED lights generate about 100 lumens per watt, ten times as many as incandescent lamps.Lumen-Candleball (cd )-Outdated, unregulated measurements.Candela (cd)-A quick check on Amazon showed that the flashlight advertised according to the amount of lumens.They start low end with 19 lumens, followed by 28 lumens, 55 lumens, 600 lumens and 2000 lumens.But what does this tell us about the flashlight.Can it tell us how bright the light will be?A flashlight on Amazon is called a 300 lumens super bright flashlight.But will lumens measure brightness?In a comment on a flashlight sold, a man said that the 2,000 lumens he bought were not as bright as his 750 lumens.He hinted that the company that produced the lamp was dishonest.One way to look at this is that both are telling the truth.It is as bright as the light of 750 lumens.A lamp of 2,000 lumens.What is the problem?The problem is related to the definition of the word lumens and people's misconceptions about this light measurement.What is lumens?.It is described as the total amount or volume of light emitted from a light source, such as a flashlight.Each lumens is a Candela (cd) or Candela power.The total light output power of the 2,000 lumens flashlight is 2,000 Candela.Think about your garden water pipe.Maximize the tap to enter the hose.Let's assume that the water flows out of the tap at a rate of 5 gallons per minute.This is the total output of water.Compared to our 2,000 lumens flashlight.At the maximum strength of the battery, the total output power is 2,000 Candela.In contrast, the light from the flashlight is like the water from the hose.When we install the nozzle on the hose, the power of the water flow can be increased.We can set it up as a narrow, powerful flow of water to wash off the mud on the tires, or set it up as a wide pattern that is good for spreading flowers.The power is very different between the two, but don't forget that the water from the tap still turns on 5 gallons per minute.But is the flashlight the same as the hose with a nozzle?Yes it does.It's called a lens.The lens focuses on light.It can be concentrated into a narrow, bright beam, or it can be turned on into a wide, relatively dark beam.But the total output is always the same, and the same is true for 2,000 lumens.So when you buy a flashlight, the amount of lumens is touted as a measure of the brightness of the flashlight, and you know it's not necessarily true.Brightness depends on the type of lens already on the flashlight.Is it a narrow focus lens or a wide focus lens?Some flashlights come with a removable lens so that the concentration of the light can change from narrow to wide, but it does not change the total output, the amount of lumens.Radiance-So there are actually two things to measure on the flashlight, aren't there?One is the total output of light, called lumens.Another method of measurement is the power of light, called radiation.It is a measurement of the effect of light on its target.Suppose the flashlight points to a person's eye.Where the light shines on the eyes.Again, compare it to the water pipe.The narrow-focused stream destroys the flowers, and the narrow-focused beam is enough to hurt the human eye.This power or power of light is its light.When we buy a flashlight, what we are really interested in is the light of the light, how bright it is.This has more to do with the lens of light than the lumen or total output of the flashlight.Now, common sense tells us that if we open the water valve completely, there is more water in the nozzle to work and focus.The less water, the less water the nozzle focuses, so there is a relationship between output and power, but the nozzle, or in the case of a flashlight, the lens, is necessary to produce electricity.The last way to understand the light emitted by the flashlight is to consider the light source and the object, or the target of the light.Lumen, the measurement of the output, is related to the light source.Radiation, the measurement of power, is measured at the object or target of the light.The next time you pick up a flashlight at the hardware store and look at the information on the package, don't fall in love with advertising gimmicks boasting lumens as brightness.Depending on the lens attached to the light, you may or may not be disappointed.If the lens is set to focus into a narrow beam, the brightness will be high.If the beam from the lens is wide, it will be very low in brightness.One way to solve this problem is to buy a flashlight with a removable lens.These lights allow the front of the light to slide back and forward, changing the focus and concentration of the light.Narrow light will be the highest light.The wide beam will be the lowest light.Why isn't the company selling flashlights explaining these concepts on the package?They may be trying to avoid confusing consumers.What they are doing is combining the output with the strength measurements to simply refer to them as lumens.This can be seen on the packaging label above."Peak intensity" was advertised as 6,000 cd.Refers to the light.Companies that sell this product believe that it is easier to combine these definitions than to explain them.I explain the way this product is advertised is assuming that the peak intensity is radiation intensity and that the high beam intensity is output or lumen.According to the packaging, this special flashlight has a "far light" which means it obviously also has a low beam of light.It seems to me that this is a good way because you are not bothered by a single intensity setting.
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