Ganesh Kumar of Heidelberg, colleague develop colour vision deficiency detection tool

A technical paper on finding a cost-effective and easy tool to detect colour blindness by Ganesh Kumar of Heidelberg India and Mohan Venkat of Sphere sight and Elite School of Optometry, has been selected for the prestigious 2019 Annual Technical Conference organised by the Technical Association of the Graphic Arts, to be held on 17-20 March in Minneapolis, Minnesota in the US. This is the only representation from India among the 35 papers to be presented during the conference.

17 Dec 2018 | By Dibyajyoti Sarma

The Daltons pseudo-isochromatic booklet developed by Kumar and Venkat

The conference will cover a myriad of research projects and innovations in graphic communications — from a study of the ability to recycle inkjet-printed products to breakthroughs in digital textile printing. The conference is presented in conjunction with the Inter-Society Color Council (ISCC).

The Technical Association for the Graphic Arts is an international association of academic and industry professionals dedicated to scientific research and technological innovation in all aspects of the diverse field of graphic communications.

The paper by Kumar and Venkat, titled ‘An evaluation to identify best printing process and substrate for newly developed colour vision deficiency diagnosing tool’ identifies the best printing process and substrate for the newly developed Daltons Pseudo Isochromatic plates for detecting colour vision deficiency by analysing durability, cost-effectiveness and repeatability of different printing processes and substrates.

Colour vision deficiency is a defect in ‘colour perception’ by the eyes. This deficiency is more common in men compared to women. Colour vision deficiency is prevalent in as many as 8% men and 0.4% women globally.

The need for colour vision testing as a routine ophthalmologic examination is well emphasised as colour vision deficiency has an impact in the choice of career/ growth in the career for a person.

The Ishihara pseudo isochromatic plates (a paper-based printed testing tool) are widely used to detect colour vision deficiency by optometrists and ophthalmologists in India and other developing countries.

“This testing tool is expensive and its print quality and paper durability gets deteriorated due to exposure to various atmospheric conditions and temperatures while using them in vision screening camps. This affects the reliability of the colour vision deficiency testing and has led to limited research data,” Kumar said.

The paper identifies the need for more affordable, reliable and durable colour vision deficiency testing tool which has the capacity to test mass population in a minimal time.

“We have done extensive research, designed and developed Daltons pseudo isochromatic plates (patent pending). We developed this new testing tool focusing on the properties and characteristics of different printing materials and printing methods to find the best durable material and printing method which can withstand different atmospheric and usage conditions in developing countries,” he added.

Kumar said the co-author of the paper, Mohan Venkat, is colour vision deficient. He aspired to become a pilot, but got rejected due to his colour vision deficiency. “So he studied optometry at Sankara Nethralaya to learn about colour blindness and his lifelong passion is to create cost-effective tool for detecting colour blindness,” he said.

Currently used detective tool, the Ishihara booklet, is printed on paper and is expensive, (up to Rs 35,000).  “As the paper ages, the life and quality of the tool goes down. Also only big hospitals have this tool and they use it occasionally. So, our idea was to create a colour blindness detection booklet which is affordable, easy to use and has a longer life,” Kumar said.

So Kumar and Venkat tested different substrates, such as synthetic paper, PE, PP, etc and different digital printing processes to find the right substrate and right printing processes. “We compared dry electrophotography presses, liquid electrophotography, UV inkjet on synthetic paper. Colour management plays a important role as it is a colour evaluation tool.  The booklet was tested for rub resistance, scratch resistance, water proof, etc,” Kumar explained, adding, “We evaluated the printed tool with colour blind people and found dry electrophotography is the most economic and high quality tool.”

The booklet is under evaluation in schools and screening camps to check repeatability and reliability.  If it’s approved by Indian Optometry Federation (IOF), soon many children who are colour-blind can be detected at earlier age.