Principle Of Optometry Red-green Tests

Squarely eye just can makes yellow of focus fell in retinal Shang, is red of focus fell in retinal Hou, green light of focus fell in retinal Qian (as Figure 2a), red and green light from retinal distance basic quite, so red and green light in retinal Shang formed of dispersion round of diameter also basic quite, so squarely eye observation red green background in depending on standard of clarity also basic same. Through a refractive correction, if properly scope, the patient will feel depending on the clarity of the same red and green. If was check who in myopia State Shi (that myopia owes straightening or hyperopia had straightening Shi), yellow of focus will fell in retinal Qian, red of focus in yellow zhihou, thus more near retinal, and green light of focus than yellow more by Qian, thus more away from retinal (as Figure 2B), so red in retinal Shang formed dispersion round of diameter to than green light small, so was check who will was red background in of depending on standard more clear. Red-Green tests, if v red sign, more clear, need to increase the degree of myopia or reducing the hyperopia, makes red and green standard is also clear.