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Flashcards in Endoscopy Deck (15)
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1

How do more fibres affect endoscopy

-Higher Resolution
-Flexibility and tighter curves without losing light

2

How does total internal reflection work?

Light had to hit boundary at angle greater than critical angle

3

Equations for Critical angle

Sinc= core refractive index/cladding refractive index

4

What happens when you increase the refractive index of cladding??

Makes a larger critical angle so more light can escape

5

What happens if you bend the fibres in a tighter curve??

Internal angle will be less than the angle of incidence at the core cladding boundary so light escapes

6

Coherent bundle -
Structure+ job

-Fibres in same relative location at both ends of the bundle
-Transmit the image of internal organs in the body

7

Incoherent Bundle
Structure+ Job

-Fibres in no fixed relative position
-Transmit light in to the human body to illuminate the organs

8

Why is cladding used
(3 reasons)

-Protects the fibres from getting scratched
-Stops light escaping from escaping from scratches
-Prevents cross talking

9

Cross talking definition

When a ray leaves one fibre and enters another.
- Lowers the resolution and blurs image

10

Laser light properties

-Monochromatic- same wavelength and F
-Collimated- parallel beams
-Coherent waves- in constant phase with each other

11

Uses of filament light in endoscopy

Illuminates inside of the body

12

Uses of laser light In body

-Stop bleeding
-Cutting tissues
-Treating tumours

13

Keyhole Surgery-what is it ?

Uses endoscopy with surgical attachments to perform operations through small holes

14

Advantages of Endoscopy

-Low risk of infection
-Greater recovery rate
-cheap
-Better cosmetics results( no scars)

15

Disadvantages of Endoscopy

-invasive