In a technique known as blue field entoptoscopy, the effect is used to estimate the blood flow in the retinal capillaries. The patient is alternatingly shown blue light and a computer generated picture of moving dots; by adjusting the speed and density of these dots, the patient tries to match the computer generated picture as well as possible to the perceived entoptic dots.
Read more about this topic: Blue Field Entoptic Phenomenon
Famous quotes containing the words blue and/or field:
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The sky was blue beyond the vaultiest phrase.”
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