Colour Blindness Types and Tests
Discover the types of colour blindness, their causes, and available tests for diagnosis. Learn about early detection and coping strategies for better adaptation.
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Last updated on 3rd Jul, 2025
Colour blindness is a condition that affects an individual’s ability to perceive colours. While some may struggle to identify specific colours, others will have a more limited colour spectrum. This condition arises primarily from nerve damage in the eyes, but there are other reasons as well. Early detection of this condition plays a key role in dealing with colour blindness. It enables individuals to adapt to their conditions and find the right coping strategies to live a peaceful life.
Types of Colour Blindness
There are three types of colour blindness which are –
Red Green Colour Blindness: This is the most common kind of colour blindness. It is mainly inherited through genetic disposition and is mostly found in males.
Blue Yellow Colour Blindness: In this case, individuals struggle to identify blue and yellow colours. But, this is not a very common type of colour blindness.
Complete Colour Blindness: This condition does not allow the patient to comprehend any colours at all. It is a very rare condition called achromatopsia.
Causes and Risk Factors
Colour blindness occurs when specific nerves in the eyes don’t respond to realise the colours as they are supposed to. Here are some possible reasons behind it –
The main cause of colour blindness is genetic predisposition. So, individuals mostly inherit it from their parents.
Sometimes, the patients experience trauma while they are young that damages the retina and leads to this condition. Also, if the foetus suffers from any impact, it can also lead to colour blindness.
Eye diseases like macular degeneration, cataracts, glaucoma or retinal damage caused by diabetes can lead to this condition.
Also, prolonged exposure to certain chemicals like carbon disulphide and lead can negatively impact colour vision.
Symptoms of Colour Blindness
Colour blindness is a condition that cannot be understood without a test. This is because the patients have always seen the colours in the same way and do not realise if anything is different. However, some visible symptoms of colour blindness are –
If the patient has trouble telling the difference between two colours and shades
If the patient finds it difficult to see the brightness of specific colours
Patients suffering from this condition face difficulties in their daily life. This is more evident when they drive, where they fail to comprehend the colours of the signal.
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Diagnosing Colour Blindness
The doctors conduct the following tests to diagnose colour blindness –
Ishihara Test
The Ishihara Test is the most popular test for diagnosing colour blindness. This test consists of colour plates containing patterns of small dots for the patients to identify. The doctor asks a few questions about the pattern, after which they are able to decipher whether the patient has red or green colour blindness and how intense his issue is.
Anomaloscope Test
According to eye doctors, the best way to identify red and green colour blindness is through a Comparison Test. In this test, an Anomaloscope is used to determine the intensity of the condition. This instrument helps determine the degree of red and green colour blindness.
Richmond HRR Test
The full name of this test is Richmond Hardy Rand Rittler Test and it is used to check for red, green, blue and yellow colour vision testing. It shows the severity of the patient by visual identification of where the symbols lie.
Colour Vision Testing Made Easy (CVTME)
This test helps to understand when children aged 3 to 6 have red or green colour blindness. They have a series of 12 plates with patterns and shapes to arrange. Usually, the first nine plates are easy, but the last three plates are tough to work on, aiding in determining this condition.
Impact on Daily Life
If a patient's intensity of colour blindness is low, he/she might not face much difficulty. However, if a patient has severe colour blindness, he/she faces serious problems, especially in his/her career, education, or personal life.
In terms of the career, especially where colour perception is crucial, it becomes challenging for the individuals. Resultantly, it narrows down the career options for them. Jobs in fields such as graphic design, electrical work, aviation, and healthcare become more challenging for them to secure.
Despite its challenges, individuals with colour blindness can adopt various strategies to navigate daily life effectively. Using labelled or high-contrast materials, relying on colour-identification apps, and arranging items in a systematic way can help overcome difficulties.
Also, people can enrol in support groups and contact all those who are already suffering from this condition.
Treatment and Management
There is no treatment for colour blindness to date. But, one thing that has come into consideration is colour blindness glasses. They increase the colour contrast and intensity, which helps the patients. However, they do not allow new colours to be shown. It should be remembered that this is not a solution for the patients. It is just a coping mechanism.
A lot of new apps and technical support have been introduced, from mobile applications to computer applications that replace the colours one is blinded from with others, making it possible for such individuals to complete the tasks.
Prevention and Genetic Counselling
Colour blindness is an inherited condition with no definite cure. It is more prevalent in males, as the X chromosomes are mostly responsible for it. Additionally, in males, the female, which is the mother, is the primary carrier. So, if a mother has colour blindness, the child has a 50% chance of inheriting it.
On the other hand, for women, it is possible if –
Both parents have this condition
If the father is a patient but the mother is not
If the father is a patient and the mother is a carrier
Research and Future Directions
Many advances in gene therapy have been made that show new directions in treating colour blindness. Here is what is available –
Targeting specific genes that are responsible for causing this condition
Clinical trials for treating genes that cause achromatopsia
Scientists finding brain plasticity in young people to adjust to new visual adaptation for colour blindness
Conclusion
Colour blindness is a condition where individuals struggle to distinguish certain colours, primarily due to genetic factors. While there is no specific cure, various coping mechanisms have been developed to help manage the condition. Since colour blindness can be challenging to detect, early testing is crucial to prevent difficulties in daily activities. It can impact routine tasks, work efficiency, and even safety. Supporting individuals with colour blindness is essential, not only to ease their challenges but also to safeguard their mental well-being.
Consult Experts for Your Eye Problems
Consult Experts for Your Eye Problems
Dr. S Venkateswaran
Ophthalmologist
35 Years • MBBS, PGD (OPTHALMOLOGY)
Tiruvannamalai
Shiva Eye And General Hospital, Tiruvannamalai
Dr. Balakrishna Balaka
Ophthalmologist
6 Years • MBBS, MS Ophthalmology
Visakhapatnam
Balakrishna eye clinic, Visakhapatnam
Dr. Jyoti Dhaka
Ophthalmologist
9 Years • MBBS, Dip in (OPHTHALMOLOGY),DNB (OPHTHALMOLOGY)
Jhujhunu
Dr.Jyoti Dhaka Eye Clinic, Jhujhunu
(25+ Patients)
Dr. Akashdipta Saha
Ophthalmologist
4 Years • MBBS, MD(Ophthalmology), Fellowship in Retina & Vitreous
Delhi
AIIMS, Delhi
Dr. Syed Saifullah Bokhari
Ophthalmologist
4 Years • MBBS, MS(Ophthalmology)
Bengaluru
Vasan Eye Care, Bengaluru
Consult Experts for Your Eye Problems
Dr. S Venkateswaran
Ophthalmologist
35 Years • MBBS, PGD (OPTHALMOLOGY)
Tiruvannamalai
Shiva Eye And General Hospital, Tiruvannamalai
Dr. Balakrishna Balaka
Ophthalmologist
6 Years • MBBS, MS Ophthalmology
Visakhapatnam
Balakrishna eye clinic, Visakhapatnam
Dr. Jyoti Dhaka
Ophthalmologist
9 Years • MBBS, Dip in (OPHTHALMOLOGY),DNB (OPHTHALMOLOGY)
Jhujhunu
Dr.Jyoti Dhaka Eye Clinic, Jhujhunu
(25+ Patients)
Dr. Akashdipta Saha
Ophthalmologist
4 Years • MBBS, MD(Ophthalmology), Fellowship in Retina & Vitreous
Delhi
AIIMS, Delhi
Dr. Syed Saifullah Bokhari
Ophthalmologist
4 Years • MBBS, MS(Ophthalmology)
Bengaluru
Vasan Eye Care, Bengaluru
