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Flashcards in Endoscope Deck (14):
1

What are endoscopes ?

They are optical instruments with long tubes that can be inserted into a body organ through an opening such as throat ,nose ,canals and anus

2

What they do and or how can it be used ?

Allow trained medical Practioners to see inside a body organ they also used during keyhole surgeries to guide the use of surgical instruments with remote handling which are incorpated into the same tube system .

3

What they do and or how can it be used ?

Allow trained medical PR actioners to see inside a body organ .

4

Steps of light endoscope being used ?

First its piped in from a source outside the body using small bundle of optical fibres

Image from inside the body is focused by an objective lens like camera

To pipe the image back out to be displayed for the medical prationer

Some shorter rigid tubular endoscopes use a series of relay lenses .

In longer flexible fibre scopes the image is also conveyed by a second fibre bundle back to an eyepiece or a camera lens .

5

What are both fibres in the protected by ?

They are protected by long ,flexible insertion tube .This tube can also came in control lines that can move the bending section at the distance end.

That is where the fibres terminate and interface with the lenses one to distribute the incoming light and the other to collect and focus the image .

6

What does it consist each fibre in the bundle is as thin as a human and consists of what >?

A core

Cladding

Protective plastic buffer coating

7

What doe keyhole surgery do ?

Keyhole surgery
Keyhole surgery involves the use of lasers with endoscopes. Lasers are useful for such surgery because:

They can shine high intensity light down an endoscope that can be focussed for cutting or destroying tissue.


They produce heat that causes the tissue around the cut to seal and prevents bleeding.



The beam is narrow and can therefore make very precise and accurate cuts.

8

When forming an image ? 1.

a tiny objective lens at the distal end of an endoscope focuses an image onto cut ends of the optical fibres in the main bundle .

9

When forming an image 2 ?

Each fibre in the bundle collects and carries the light for one pixel coloured dot in the image .

10

When forming an image 3 ?

An eyepiece lens a the operator end takes the light existing from the fibre bundle and refocuses it to be viewed as an image directly by eye or with a camera .

11

Analogue images

Even though its divided by pixels these images are analogue this is because of the brightness and colour of each pixel vary with time in direction proportions to the light collected by the objective lens .

12

Illumination

A small fibre bundle is used for piping the light form external sources down to the remote are where it illuminates the are being investigated.

13

What does the cladding do ?

Cladding provides a lower refractive index at the core interface to cause reflection within the core and light are transmitted through the fiber. To preserve the fiber strength coatings has multi layers of plastics.

Cladding is used in optical fiber for prevent any refraction while passing data.


Cladding Is less dense like plastic for example .






14

What does the cladding do ?

Cladding provides a lower refractive index at the core interface to cause reflection within the core and light are transmitted through the fibbers. To preserve the fibre strength coatings has multi layers of plastics.

Cladding is used in optical fibre for prevent any refraction while passing data.


Cladding Is less dense like plastic for example .