In humans, our perception of color is closely linked to the wavelength of light. Within the visible spectrum, red is associated with longer wavelengths, green falls in an intermediate range, and blue and violet correspond to shorter wavelengths.
The human eye can perceive this electromagnetic radiation within a wavelength range of approximately 380 to 780 nanometers. Individuals with normal color vision can distinguish around 150 different intervals (or colors) within this range. Color is determined intrinsically by the wavelength of monochromatic light, and our perception of color involves three main factors: hue, saturation, and brightness. Notably, our ability to differentiate between various hues (or wavelengths) is more accurate in the middle range of the visible spectrum compared to its boundaries.
From a scientific perspective, detecting these subtle differences in wavelengths within a color is highly interesting and challenging. Whit that in mind we developed a novel instrument to measure this wavelength discrimination threshold. This instrument utilizes a Tungsten-Halogen lamp as source of the visible spectrum. This light is then collected and split in two independent arms. In each arm the presence of independent automatized monochromators allows for a precise control of the transmitted wavelengths. A test software is used for running the system and an automated experiment. This is done by showing the two independent light outcomes from the monochromators that can be manipulated to be equal or distinct, allowing for an accurate discrimination at the nanometer level. This allows us for measuring the wavelength discrimination threshold across the entire spectrum, and then establish a function that describes an individual’s color discrimination threshold.
Several studies where then proposed and conducted to access several types of color deficiency and age-related changes in this threshold.