Ainun Najwa Aqilah Binti Mohamad Razaki, B. Optom

Student, Management and Science University, Malaysia



Colour vision deficiency/colour blindness is not 100% blindness, rather it is a deficit in the perception of colour. Colour blind people have trouble differentiating between hues, such as blue-yellow or red, green. Colour blindness is a hereditary disease that affects men more than women. According to the study, colour vision issues affect around 8% of men and fewer than 1% of women. Red-green deficiency is the most common colour deficiency. Blue-Yellow deficiencies are very rare but can affect both men and women (Kozarsky, 2020).


Diagnosing colour blindness can be accomplished through various methods. The Ishihara test is a red-green colour blindness screening test. Plates with dots of various colours and sizes are shown to you by the doctor. One or two-digit integers and geometric forms can be found among the dots. Shapes in red and green may be difficult or impossible to see if you cannot perceive colours (Stresing, 2008) .

Next, the Cambridge colour test. During this test you look at a computer screen instead of a person. For the “C” form, you will look for a shade of colour that contrasts with your surroundings. It appears out of nowhere. You then press one of four buttons when it appears. The Anomaloscope follows. A circle is visible when viewed via an eyepiece. Yellow light fills the upper half of the circle. Red and green lights fill the bottom part of the screen. To achieve the same hue and brightness in both parts, you adjust the knobs on either side. To determine if someone has problems seeing red and green, doctors utilise this test. The Farnsworth-Munsell 100 hue test follows. This technique makes use of blocks or pegs in a variety of hues of the same colour (Brennan, 2020). 

 Figure 1: Ishihara Colour Blindness Test (Kamińska et al., 2017 ; Kumar et al., 2021)

You must arrange them in a specific order. You’ll see if you can detect subtle colour shifts with this test. If a company relies on the ability of its personnel for colour vision, they may leverage it. Lastly, the Farnsworth Lantern Test, or FALANT, is a colour vision test designed to screen sailors for duties that require colour vision, such as spotting night-time signal lights. It detects red-green colour deficiencies, but not the uncommon blue colour deficiency (Bailey, 2019).


Management of colour vision abnormalities can be corrected by using colour blind glasses. Tinted glass based on the type of colour blindness helps those CVD people to differentiate colour by filtering specific wavelengths through the proprietary optical material of the glasses. However, these glasses do not produce 100% normal colour vision nor cure colour blindness (Libers, 2020). They correct certain colour vision deficiencies of colour blindness only. Dyed contact lenses can be used to filter out certain colour. Tints like sulphur, vat, reactive and Rhodamine dyes are used in tinting contact lenses that are specially manufactured for CVD management (Konkel, 2006).

Smartphone and computer apps or features also can be used in management of CVD. For example, Microsoft has added a colour filter feature to Windows 10 where the CVD users are able to alter the colour of the screen to enhance their colour perception (Figure 2).

Figure 2: Microsoft colour filter feature (Retzke et al., 2017 ; Bondarchuk et al., 2020).


Colour blindness is a disability due to cone dysfunction. When compared to normal people, this results in distorted vision, reducing the visible spectrum and altering the appearance of the colour. Colour blindness changes your life, but many people overcome their problems and adjust their daily routines to cope with colour blindness. Getting your eyes tested regularly helps you know if you have a colour vision deficiency.


I would like to thank my friends and the students of Bachelor of Optometry at the Management and Science University, Malaysia, Rohdatul Sakina, Yong San and Kavita for helping and giving equal contribution for helping me write this blog.



  1. Bailey, G. (2019, February 27). Color Blindness Explained. All about Vision.
  2. Bondarchuk, О. Balakhtar, V., & Balakhtar, K. (2020). Monitoring of the quality of the psychological component of teachers’ activity of higher education institutions based on Google Forms. E3S Web of Conferences, 166, 10024.
  3. Brennan, D. (2020, January 14). What You Need to Know About Color Blindness Tests. WebMD.
  4. Kamińska, D., Sapiński, T., Kucharczyk-Pośpiech, M., & Wilczynski, M. (2017). Ishihara Color Test Using a Mobile Virtual Reality Headset for Immobilised Patients. Roczniki Kolegium Analiz Ekonomicznych, 46, 2017.
  5. Konkel, L. (2006, May 6). Color Blindness Treatment & Solutions. EverydayHealth.Com.
  6. Kozarsky, A. (2020, September 1). Guide to Colorblindness. WebMD.
  7. Kumar, A., Ar, L., Dathan, P., & Nair, C. (2021). Basics of Colour Science and Prosthodontics -A Review. 5, 2581–4893.
  8. Libers. (2020, September 22). What Is Color Blindness? Symptoms, Causes, Diagnosis, Treatment, and Prevention. EverydayHealth.Com.
  9. Stresing, D. (2008, June 10). Color Blindness. EmpowHER.