The tests which are used in screening are Ishihara test plate, Nagel anomaloscope
test, Farnsworth-Munsell hundred hue test but except Ishihara test all other tests are time consuming and cannot be used for mass screening.
The limitations of our research were the small size of samples and the diagnosing method was not conducted with more quantitative tools, that is, anomaloscope
. However, future studies need to be designed to determine the etiology related to why people see color information achromatically in the procedure for measuring stereopsis.
As males have only one X chromosome therefore they are more prone to this disorder.18 On the other hand as females have two X chromosomes therefore they can be carriers but a low prevalence is found.18 Ishihara test, D15 and anomaloscope
are used for diagnosis of CVD.
For further diagnosis anomaloscope
is used but it can only be used in healthcare settings.
Color vision tests for aviation: comparison of the anomaloscope
and three lantern types.
Both exhibit a capacity to find a specific point of reference in the anomaloscope
test (unlike those suffering from dichromacy who cannot settle on a single equilibrium point).
All were screened for normal colour vision by means of the Ishihara Pseudo-Isochromatic colour plates, the City University Colour Vision Test (CUCVT; Fletcher, 1980), the "Test para Identificacion de los Daltonismos" (TIDA [Test to Identify Colour-Blindness]; Lillo, 1996), and Rayleigh matches on an anomaloscope
TABLE 1: Color Vision Deficient Groups Extent Selection Criteria Deutan Protan Mild anomalous Pass Farnsworth lantern, pass 5 5 trichromats Farnsworth-Munsell Panel D-15 Moderate anomalous Fail Farnsworth lantern, pass 5 5 trichromats Farnsworth-Munsell Panel D-15 Strong anomalous Fail Farnsworth-Munsell Panel 5 5 trichromats D-15 (but not dichromats or extreme anomalous trichromats (a)) Dichromats Match whole red-green range on 10 9 Nagel anomaloscope
even after adaptation on Trendelenberg plate Note.
examination is based on metameric matching principles.
The Nagel anomaloscope
was recommended to confirm the identification of protan deficiency if required.
In 1881, Lord Rayleigh introduced anomaloscope
for scientific analysis of color defects (5).
In addition to the battery of chromatic clinical tests previously described, the protanopes' clinical status was confirmed using a Nagel anomaloscope