6. USE
• Vision
• Pupil Size
• Pin hole
• ‘ring’ of light that encircles the sun
• LIT. ROOM
• SOUND
7. Polarization
• Polarization, in Physics, is defined as a phenomenon caused due to
the wave nature of electromagnetic radiation.
• Unpolarized light is a haphazard mixture of polarized beams of light
directed in various planes. A mixture of polarized light and
unpolarized light is termed unpolarized light.
12. Application
• Ophthalmic instrument (e.g Slit lamp)
• Polarizing Projection charts
• Three-dimensional picture
• Polaroid sunglasses
• Titmus fly test
• RNFL layer thickness
• Detection of defects in the intra-ocular lenses may be done by using
the principle of Birefringence
16. • Fluoresceine dye when exposed to light by a fundus camera, then
unbound fluorescein absorbs light of a wavelength in the range of –
465-495 nm. Which is a bluish region
• Clinical applications:
• Fluoreceine angiography is used in performing fundus angiography
and various other angiography done for diagnosing ocular, cardiac,
cerebral, and liver conditions.
17. Double Refraction (Birefringence)
1969 (Erasmus barthulinus)
• Birefringence is the phenomenon exhibited by certain materials in
which an incident ray of light is split into two rays, called an ordinary
ray and an extraordinary ray, which are plane-(linear) polarized in
mutually orthogonal planes, or circular-polarized in opposite directions
(left and right)
• (1) Calcite crystal
In prism you will see, only only refractive ray and in Calcite crystal 2 rat
