How are optical Fibres used in medicine?
The most significant and prevalent applications of fiber optics in medicine are in the imaging and illumination components of endoscopes. Low-loss optical fibers are employed to transmit laser energy for surgery and photocoagulation.
How does light propagate through an optical fiber?
In optical fibers, propagation of light takes place due to total internal reflection. When light falls one end of the optical fiber; it gets refracted into the fiber. The refracted ray of light falls on the interface separating the fiber and coating an angle which is greater than the critical angle.
What is propagation in optical fiber?
Fiber-optic cable has two propagation modes: multimode and single mode. When the light wave is guided down a fiber-optic cable, it exhibits certain modes. These are variations in the intensity of the light, both over the cable cross section and down the cable length.
What type of electromagnetic wave is used in optical fibers in medical uses?
In several applications such as optical fiber transmission, the electromagnetic radiation ranges from 850 nm, 1310 nm, and 1550 nm, where it is called the near infrared range.
Can optical fibers be used in communication in industry and medicine?
Applications. Optical fiber is used by telecommunications companies to transmit telephone signals, Internet communication and cable television signals. It is also used in other industries, including medical, defense, government, industrial and commercial.
Why do we need optical instruments in field of medicine?
As such, optics, as the science that studies the behavior and manipulation of light and images, is an ideal tool to assist doctors gain better visual examination capabilities by providing improved illumination, magnification, access to small or internal body cavities, among others.
What is light propagation?
Light propagates as an electromagnetic wave inside the optical fiber. This wave can propagate either in one mode, i.e., “single-mode fiber” or in multiple simultaneous modes, i.e., multimode fiber (Figure 4a). Optical fibers with a smaller core allow only a single mode; larger fibers allow multiple modes.
What are the factors which affect the light propagation through the optical fiber?
It depends on the core radius, the numerical aperture of the core and the wavelength of light stimulating the fibre.
What are the types of light propagation in optical fiber?
The three most widely used types of fibre-optic cables are multimode step-index, single-mode step-index, and multimode graded-index. If we want to transmit only single mode, then normalized frequency must be in the range 0 ≤ v ≤ vc, where vc = 2.405.
Which light is used in optical fibers?
Laser light is used for optical fiber communications for the simple reason that it is a single wavelength light source.
What wave is used in optical fiber?
Visible light and infrared waves are used in optical fibres. An optical fibre is a thin rod of high quality glass. Light goes into the glass at one end and it undergoes repeated total internal reflection, even when the fibre optic is bent. The light in the fibre optic never leaves the glass and is constantly reflected.
What is an optical Fibre write any two uses of optical fiber in medical sector?
Optical Fibres uses in Medical industry Because of the extremely thin and flexible nature, it used in various instruments to view internal body parts by inserting into hollow spaces in the body. It is used as lasers during surgeries, endoscopy, microscopy and biomedical research.
What kind of rays can propagate along an optical fiber?
Two types of rays can propagate along an optical fiber. The first type is called meridional rays. Meridional rays are rays that pass through the axis of the optical fiber. Meridional rays are used to illustrate the basic transmission properties of optical fibers.
Which is the best description of light propagation?
The concept of light propagation, the transmission of light along an optical fiber, can be described by two theories. According to the first theory, light is described as a simple ray. This theory is the ray theory, or geometrical optics, approach.
Why does light not propagate along a fiber?
However, not all wave fronts incident on the fiber at angles less than or equal to the critical angle of light acceptance propagate along the fiber. Wave fronts may undergo a change in phase that prevents the successful transfer of light along the fiber. Wave fronts are required to remain in phase for light to be transmitted along the fiber.
What is the acceptance cone of a fiber?
The light ray incident on the fiber core must be within the acceptance cone defined by the angle -a shown in figure 2-13. Angle -a is defined as the acceptance angle. The acceptance angle (-a) is the maximum angle to the axis of the fiber that light entering the fiber is propagated.