Introduction to Optical Dispensing

With refractive errors being one of the most common eye disorders, its correction, especially by spectacles,is in great demand. Refractive correction can be brought about by spectacles, contact lenses and refractive surgery. However spectacles are still the preferred choice - largely because they are cheaper and easier to dispense. Hence in this module, ‘optical dispensing’ will usually refer to the issue of spectacles.

Proper dispensing of a pair of spectacles begins with an accurate prescription. It also includes guiding the patient to choose frames and lenses that are comfortable, affordable as well as aesthetically suitable. The quality of the lens and its fitting also affects the correction provided. In addition to these, proper counselling about use and maintenance can ensure proper uptake of the correction. It is important to design the optical dispensing system itself in order to make it sustainable and efficient. A few guidelines have been included in this module.

This module deals with the different aspects of optical dispensing - such as patient counselling, order processing, fitting of the lenses and stock keeping. Basic information about frames, lenses and their types has also been provided. This module targets the training in the following skills:

1. To guide the patients to choose appropriate frames and lenses
2. To do lens surfacing and glazing with scientific methods by manual and automatic processes
3. To troubleshoot the problematic spectacles
4. To do the frame measurements, centering and de-centering techniques
5. To inspect lens defects
6. To organise optical dispensing services in community outreach programmes

Refraction, with the help of a trial set and Snellen’s chart, is a simple and effective method to identify those with errors. And correction, by spectacles, is an easy and affordable solution. Yet, in most developing countries, where people do not readily seek health services especially for non-critical problems, the challenge lies in identifying and reaching out to the patient and providing the refractive correction.

Lack of awareness and inaccessibility of affordable optical services have been indicated in WHO surveys of blindness and visual impairment worldwide. Uncorrected refractive errors could lead to amblyopia in children and may lead to visual loss. Such avoidable blindness can be easily prevented by wearing appropriate spectacles. Aravind Eye Care System, with the help of about 1500 outreach camps a year, reaches out to the people and identifies and treats those with eye problems. Those identified to have refractive errors can buy a pair of glasses and it is fitted and delivered to them on the spot. This module also explains this system of spectacle dispensing at campsites.

It is recommended that dispensing opticians also need to know about the following topics, which are outside the scope of this manual:

1. The eye and the way it works
2. Refractive Errors
3. Corrective methods including surgery
4. Contact lenses (only basic information is given in this manual)
5. Low vision aids (only basic information is given in this manual)
6. Optical accessory products such as cleaning agents for contact lenses, spectacle lenses, frames and sunglasses
7. Fashion trends for frames and sunglasses
8. The construction of frames, the materials used and the design characteristics
9. Business management
10. Practical aspects of edging and surfacing of lenses
11. Up-to-date information about new optical products available in the market