According to eHealth, 550 million people have vision problems in India, 80% of whom could be treated if the problems can be identified at the early stage.

Slit lamp is a medical device which is used for the diagnosis the eye related problems like:
- Clouding of the lens (cataracts)
- Injury to the clear tissue (cornea) that covers the front of the eye
- Dry eye syndrome
- Loss of sharp vision due to macular degeneration
- Separation of the light-sensitive membrane (retina) in the back of the eye from its supporting layers (retinal detachment)
- Blockage in a small artery that carries blood to the retina (retinal vessel occlusion)
- Damage to the retina

It is an instrument consisting of a high-intensity light source that can be focused to shine a thin slit of light into the eye. Currently available slit lamps are big and very expensive. They have a very complex structure. There are some portable ones also available but they are also very expensive.

My solution is a lightweighted and inexpensive 3D Printable Slit Lamp with fewer components. It can be transported and repaired easily as well. This device will be really helpful for people living in rural areas who are not able to get good medial services.

To ensure my device functions as expected, I've compared my design to the professional standard "Keeler PSL Classic Portable Slit Lamp."
 
- Diagnosis Accuracy - Proposed design is head mounted rather than desk mounted, which improves its diagnosis accuracy over the Keeler.

- Portability - Proposed design is lightweighted and can even be printed on site.

- Dials - Both slit lamps have two dials, one for changing the slit size and one for changing the filters.

- Lens Resolution - The Keeler features 10x and 16x viewing lenses. The lens resolution of the proposed design has replaceable viewing lenses, which include 10x, 16x and more.

- Accessibility - The Keeler features proprietary custom made parts that require professional manufacturing facilities. The proposed design is open source and printable using any desktop 3D printer.

- Cost - The cost of the Keeler is £4,095, whereas the 3D printable slit lamp costs less than £100.

3D Printable Portable Slit Lamp:

The design is so that it facilitates portability to the user. With minimum number and very fundamentally designed components, this can be taken along/printed at your desired place.

It is comprised of:

i. A head-strap which can directly be worn by the patient with ease of adjustability and usage.

ii. Slit Dial, which is of 12mm length with varied width options (0.2, 0.4, 0.6 1.6mm)

iii. Filter Dial, which consists of five different kind of filters
•Red free
•Blue
•Neutral Density: 0.8
•Clear
•IR heat absorbing
iv. Light Source, a 4W, 300lm LED torch
v. Eye Piece, 15X magnification lens

Proposed design would be an open source design under the "CERN OHL" licence.