How do EnChroma glasses help in correcting color blindness?
To understand this, we have to understand the concept behind color vision and color blindness. We see images with the help of photoreceptor cells present in the retina. We have two types of photoreceptor cells present in the retina. They are rod cells and cone cells. Rod cells help in night vision. Cone cells help in seeing colors.
We have three types of color-sensing cone cells in our eyes. They are red, green, and blue cone cells. Each of these three cone cells have overlapping regions in the spectrum of light they absorb. Whenever the overlapping of the spectrum is broader, it results in poor color differentiation. This condition is called color blindness. It is also known as color vision deficiency (CVD).
There are different types of color blindness ranging from partial-to-complete color blindness. People with CVD have difficulty differentiating between colors such as yellow and orange, green and brown, pink and gray, or blue and purple. This inability to distinguish the colors is called red-green color blindness. The other type of color blindness is blue-yellow color blindness. It is due to the inability to see shades of blue and confusion between blue and green colors. In very rare cases, a person can be completely color blind.
Definition of EnChroma
Now, let's understand the concept behind the name EnChroma glasses. En- is the prefix, which means "within." Chroma is defined as the intensity of a distinctive hue or saturation of a color. These glasses filter the light with a specific wavelength to reduce the spectrum's broader overlapping to keep it within a specific spectrum of colors. Thus the name EnChroma glasses.
To understand more about Chroma, you can refer to Munsell Chroma.
Evolution of EnChroma Glasses
Having understood the concept behind color blindness and EnChroma glasses, let's delve into the details of the idea used in the filters that coat EnChroma glasses and the type of color blindness it corrects.
The filter used to eliminate the overlapping of the wavelengths of light is called optical interference filters.
There are two types of optical interference filters. They are narrow notch and multi-notch filters. These filters are primarily used in Raman spectroscopy and laser-based fluorescence. These applications require filtering different wavelengths to pass the required wavelength of light through the spectroscopy to carry out the desired experiments.
The same principle is used in EnChroma glasses, which uses multi-notch filters to strongly suppress one or more wavelengths or narrow bands of wavelengths and maintain higher transmittance of nearby wavelengths. This suppression or cutouts in the visible spectrum help to enhance colors and correct color blindness.
Type of Color Blindness Corrected by EnChroma Glasses
The EnChroma glasses reduce overlapping regions between red and green cone cells by using a filter. This helps to improve the color vision in people suffering from red-green color blindness.
EnChroma glasses help to correct red-green color blindness like any vision correction glasses that correct the vision. It does not cure any color blindness.
It does not correct any other color blindness.
After wearing the EnChroma glasses, it usually takes between 5 to 15 minutes to see the colors.
You have to wear these glasses all the time, like vision correction glasses.