The Mars Letter Contrast Sensitivity Test
 |
News
- Our international shipping rates have been greatly reduced! Request a shipping quote here!
- Two very positive evaluations of the Mars test have been published in 2005 and 2006 in the scientific literature. We are now delighted to announce that a third evaluation conducted at Moorfields Eye Hospital in collaboration with University College, London has been accepted for publication in the British Journal of Ophthalmology for 2007. All three papers are available on the downloads page.
- A set of approximate norms for use with the test is now available for download here.
- Article describing the design of the Mars test published in Investigative Ophthalmology & Visual Science. Read it here.
|
The Mars Letter Contrast Sensitivity Test, the most accurate and convenient contrast sensitivity test available, is now being sold direct to
ophthalmologists, optometrists, eye clinics and vision researchers.
Unlike many other contrast tests that merely assess visual acuity using low contrast
targets, the Mars test is a true contrast sensitivity measure that
indicates the
lowest contrasts your patients can perceive, rather than the smallest
letters they can identify at some low, arbitrarily chosen contrast.
With the Mars test, it is the contrast, and not the letter
size, which diminishes from the beginning to the end of the chart.
The letters
are large, insuring that most patients, even those with low vision,
can see them.
And because research has consistently shown that large
letters are identified by the most sensitive of
the visual system's
size-tuned spatial frequency channels, the Mars test accordingly
yields the sensitivity of the most sensitive channel, and of the visual system as a whole.
Uses
- Establishing baseline contrast sensitivity prior to and after an intervention
(such as cataract extraction, LASIK, or other refractive surgery)
- Identifying functional losses in low contrast perception
(often associated with glare sensitivity)
- Monitoring effects of disease progression on function
Features and Benefits
- Three charts, for the left eye, right eye and binocular testing,
or for repeated testing without letter sequence memorization
- Rapid administration, with easy, accurate scoring
- Easy to store and protect
- Easy to illuminate (e.g., with instrument stand lamp)
- Each chart mounted on durable plastic
- Designed for near testing (40 or 50 cm)
- Low cost