Luminous efficiency function
Have you ever noticed that some light bulbs are brighter and some are dimmer? Do you know why that is? Well, scientists have come up with something called a "luminous efficiency function" to help them measure how well our eyes see different types of light.
The luminous efficiency function basically measures how effective different wavelengths of light are at stimulating our eyes to see. You see, our eyes are most sensitive to light with wavelengths around 555 nanometers (that's really just a fancy way of saying a specific type of light that our eyes can see well). So, the luminous efficiency function takes this sensitivity into account and assigns values to different types of light based on how well our eyes can perceive them.
For example, light with a wavelength of about 650 nanometers (that's a reddish-orange color) is not very efficient at stimulating our eyes to see. So, even though a light bulb might be bright and emit a lot of reddish-orange light, it won't necessarily look very bright to our eyes because our eyes aren't very sensitive to that type of light.
On the other hand, light with a wavelength of about 555 nanometers (a yellowish-green color) is very efficient at stimulating our eyes to see. So, even if a light bulb emits less light overall but more of that yellowish-green light, it might actually look brighter to our eyes than a light bulb with more overall light but less of that yellowish-green color.
So, the luminous efficiency function helps us understand how well our eyes are able to see different types of light and how we can use that information to make better lighting choices.
The luminous efficiency function basically measures how effective different wavelengths of light are at stimulating our eyes to see. You see, our eyes are most sensitive to light with wavelengths around 555 nanometers (that's really just a fancy way of saying a specific type of light that our eyes can see well). So, the luminous efficiency function takes this sensitivity into account and assigns values to different types of light based on how well our eyes can perceive them.
For example, light with a wavelength of about 650 nanometers (that's a reddish-orange color) is not very efficient at stimulating our eyes to see. So, even though a light bulb might be bright and emit a lot of reddish-orange light, it won't necessarily look very bright to our eyes because our eyes aren't very sensitive to that type of light.
On the other hand, light with a wavelength of about 555 nanometers (a yellowish-green color) is very efficient at stimulating our eyes to see. So, even if a light bulb emits less light overall but more of that yellowish-green light, it might actually look brighter to our eyes than a light bulb with more overall light but less of that yellowish-green color.
So, the luminous efficiency function helps us understand how well our eyes are able to see different types of light and how we can use that information to make better lighting choices.
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