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Rods, Cones, and Light definitions

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  • Opsin
    A protein pigment in the eye that absorbs light, enabling the perception of different wavelengths.
  • Rhodopsin
    The opsin used by rods, absorbing light best at 500 nanometers, crucial for grayscale vision.
  • Rods
    Photoreceptor cells in the eye that perceive light in grayscale using rhodopsin.
  • Cones
    Photoreceptor cells in the eye that perceive color using three types of opsins.
  • Short Wavelength Cone
    Also known as the S or blue cone, it absorbs light best at 420 nanometers.
  • Medium Wavelength Cone
    Also known as the M or green cone, it absorbs light best around 535 nanometers.
  • Long Wavelength Cone
    Also known as the L or red cone, it absorbs light best at 565 nanometers.
  • Color Perception
    Arises from comparing the relative signals received from all three types of cones.
  • Electromagnetic Radiation
    Light is a form of this, with wavelengths between 387 and 700 nanometers.
  • Wavelength
    The distance between successive peaks of a wave, crucial for determining light color.
  • Relative Absorbance
    A measure of how much light a photoreceptor absorbs at a given wavelength.
  • Color Blindness
    A condition where certain colors cannot be distinguished, often due to cone deficiencies.
  • Graph Interpretation
    Understanding graphs of wavelength versus absorbance is key to grasping color vision.
  • Signal Pattern
    The unique combination of signals from cones that the brain interprets as a specific color.
  • White Perception
    Occurs when all three cones are equally excited by a bright mix of wavelengths.