Prism power Prism power is the amount of light displaced in centimetres at a distance of 1m away from the prism or lens. Prism power is denoted by Δ Δ = Image displacement in centimetre / 1 Meter Suppose a plus lens is decentred downward. The parallel ray instead of passing through the optical centre … Read more
Many mechanisms exist to protect the eye from external injury. Mechanism of potential damages to the eye can ocular as: 1.Protection from mechanical damage The orbit: The eyelids: The corneoscleral shell 2.Protection from chemical damage Eyelid closure Bell’s phenomenon Tears Corneal epithelial barrier 3.Protection from biological damage Tear film and conjunctiva: Corneal epithelium and Bowman’s … Read more
Introduction In a few cases of prism prescriptions, where both horizontal and vertical prisms are required to correct the deviation. In such a case, one single prism can be computed in the manufacturing process to have the exact same result as the combination of the two specified prisms. Compounding prism Compounding prism refers to the technique … Read more
Prism orientation Unlike cylindrical lenses where the axis of cylindrical lenses is noted from 0 to 180, prisms have a base direction throughout 360 degrees. Whereas, a cylindrical lens axis of 90 degrees is similar to 270 degrees but in the case of a prism if the base orientation is toward 90 degrees it is … Read more
Prisms are wedge-shaped lenses that divert light towards their bases without altering their vergence. An optical prism is a transparent solid device that bends light. It is often composed of glass or plastic. It has two flat surfaces that are usually inclined with one another, as well as a surface that isn’t parallel. A prism can … Read more
Cataract is one of the major eye health disorders in the World leading to blindness and India is no exception to it. According to NPCB, Cataract alone is responsible for 62.6% of blindness among the Indian population. Cataract comes under avoidable blindness, which can be successfully treated with a surgery. The lack of basic eye … Read more
Eye cosmetics are meant to enhance the appearance of the eye thus making it more attractive. It is believed that it boosts the confidence level of people. Currently available eye cosmetics in the market include liquid eyeliner, pencil eyeliner (Kajal), eyeshadow, glitters, eyebrow pencil, artificial eyelashes with glue, mascara, concealer, etc. Eye cosmetics are used … Read more
What is a Toric lens? A toric lens is defined as a lens which has one surface toroidal (one of the principal meridians is more curved than the other principal meridian) and another surface of the lens is spherical (convex or concave). What is Toric transposition? It is a method which enables, the Toric lens … Read more
Holi is a celebration of colour, joy, getting together with family and friends, and food. Everyone in the nation is eager to celebrate Holi with their loved ones now that it is just around the horizon. Holi is a festival where people apply or throw colour at one other, yet most of us seldom ever … Read more
The keratometer is a specialized instrument used by optometrists and ophthalmologists to measure the curvature of the cornea. This measurement is important because it helps optometrists/ophthalmologists diagnose and manage a variety of eye conditions, such as astigmatism and keratoconus. In this blog post, we will discuss what a keratometer is, how it works, and why … Read more