Flexible Endoscope Accessories

Endoscopes, including flexible ones, are essential tools for minimally invasive screening, diagnostic and therapeutic procedures.

As part of routine cleaning and reprocessing, endoscopes should be inspected for defects, visible soil, and moisture to ensure that they are free of damage that could impact patient outcomes.

Fiberoptic Bundles

A fiberoptic bundle is an assembly of multiple optical fibers. These are available in many configurations and can be used for a variety of applications.

For example, they can be used to redistribute light input to create a more uniform output at the end of the bundle. They can also be used to split or combine different signals, such as image information and spectral analysis.

The cores of these bundles are usually multimode, allowing for more information to be transmitted through them than with a single-mode fiber. This is important for imaging and spectroscopic applications, where the amplitude of a particular mode may be more important than its intensity.

Bundled fiber assemblies can be fabricated from small core (100um) or large core (over 1mm) silica and plastic optical fibers. A common configuration is to assemble fibers in a circular fashion on one end, and stack them linearly on the other. This configuration is often used in spectrometers for analyzing near-infrared (NIR) transmission spectra. It is called a “round to slit” configuration.

Illumination Lenses

Illumination lenses are used in endoscopes to direct or spread out light sources. They can be single or multiple source and are often flexible. They can be used in many different applications, including directing fiber optic light guides, focusing assemblies, LED spot lights, and incandescent light or line lights.

They can also be used to illuminate surfaces that are not directly visible through the lens, such as light-absorbing or reflective objects. These types of illumination can be critical to accurate imaging and image quality.

Unlike conventional backlight illuminators, telecentric illuminators have collimated rays Flexible endoscope accessories that do not scatter off specular edge features or cause glare, allowing the underlying surface to be illuminated without a shadow (Figure 4).

They can also be used to adjust the vignette effect – shading of the outer edges of the image. This can be especially useful for high-angle applications, where a vignette can be an obstacle to proper image clarity.

Optical Fibers

Optical fibers are an important component of many flexible endoscope accessories. They transmit light signals and video images, resulting in high-resolution visualizations of internal anatomy with greater diagnostic confidence.

Unlike copper wires, which carry electricity, optical fibers transmit only light. This makes them ideal for telecommunications, where they can deliver higher speeds and more bandwidth than electrical cables.

In addition, they are relatively sturdy and can withstand pressure far better than copper cable. These features make them a viable alternative to copper cable for data transmission, especially in large-scale business settings.

An optical fiber has a core and a cladding of different materials that work together to reduce the refractive index (the rate at which light travels through an object). The cladding is usually made from plastic, while the core is often made from glass.

A common cladding material is silica glass. The refractive index of silica glass varies with the frequency of light, meaning that rays entering the fiber at different frequencies will travel at different rates. This can cause problems over long distances, as different frequencies may take slightly longer to reach the receiver than others.

Optical Fiber Guides

Optical Fiber Guides provide a means of connecting endoscopic devices to the light source. They are made of medical cable and have a number of sizes from 3.5 mm to 2.3 meters in length.

Unlike incandescent lights, optical fibers do not produce heat or emit ultraviolet (UV) radiation. Instead, light travels through the core of the fiber via total internal reflection, bouncing back and forth off the boundary between the fiber’s cladding and core.

The wavelength of the light and the diameter and index of refraction of the core determine the number of modes that can propagate in an optical fiber. This number is called the numerical aperture and a high NA means that light can enter the fiber at multiple angles.

Optical fibers are typically single-mode or multi-mode, depending on the application. Single-mode fibers have a smaller core diameter than multi-mode, making them more sensitive to vibrations and shocks.

Optical Fiber Tip

The Optical Fiber Tip is a versatile microcomponent that can be formed directly at the end of an optical fiber to change the emission behavior of the fiber. It can be used in a wide variety of applications, including biomedical imaging and tissue removal.

The fiber tip is a plasmonic metasurface (MT) with a gradient-index profile that impresses a linear-phase component in the wavefront of an impinging beam, yielding splitting in transmitted and reflected waves. In reflected beams, the anomalous component undergoes a phase-gradient-induced steering of an angle.

These devices can be fabricated using a variety of microfabrication technologies, including photolithography [16,17], nanoimprinting, interference lithography, electron-beam lithography, and direct focused ion-beam milling. However, they have a number of limitations.

The high aspect-ratio and small cross-section of the flat tip of an optical fiber challenge established fabrication techniques, which are better suited to large planar substrates. This review discusses numerous strategies to pattern the flat tip of an optical fiber, including self-assembly, multiple lithographies, through-fiber patterning, and hybrid techniques. It also discusses diverse optical fiber tip applications in Biology/Medicine, including plasmonic biosensors, polarization-sensitive devices and fiber-optic sensors for gas pressure monitoring.

Optical Fiber Shaft

The Optical Fiber Shaft is an extremely flexible endoscope accessory, which allows you to easily inspect areas inaccessible by standard inspection tools. The shaft is made of a high-modulus, low-density polymer and features multiple fiber Bragg grating (FBG) sensors embedded along its length.

Despite their popularity, optical fibers are prone to bending losses when subjected to abrasion or mechanical strain, which can be especially common with patchcords and fiber optic cables in tight enclosures such as a patch panel. Several fiber manufacturers offer bend-insensitive (BI) singlemode and multimode fibers that are more tolerant of bending loss than conventional fibers.

Most BI fibers are glass with a higher index of refraction than their cladding, which allows total internal reflection to trap light in the core up to a certain angle. The angle at which this occurs is called the critical angle.

Aside from the fact that BI fibers are very flexible, they also have a smaller numerical aperture than other types of fibers, which is a measure of how much light can enter and travel in the core of the fiber before it reaches its surface. Consequently, BI fibers are often used in applications where precision is important such as splicing or termination.

Optical Fiber Insertion Tube

The Optical Fiber Insertion Tube is designed to attach an optical fiber end Flexible endoscope accessories to a connector for use in medical imaging. This flexible device is much less invasive than traditional open surgery, as it only requires a small incision in the body and can be used by a doctor at home or by an outpatient department.

Historically, glass fibers were arranged end-to-end with no covering at all to increase the refractive index of the glass and therefore increase light transmission through total internal reflection (TIR). When water or dirt was introduced into the fiber, this change in the glass-air interface caused water or dirt to be reflected back into the fiber, thus changing the overall reflection.

In the 50s, Dutch Abraham van Heel introduced a cylinder of glass, of lower refractive index than the one in the middle, to protect the fiber from water and prevent the total internal reflection of light to be changed. This cladding was also able to control the temperature of the core and therefore improve the thermal stability of the fiber.

Optical Fiber Endoscope

The Optical Fiber Endoscope is an advanced instrument that allows doctors to view the internal organs without having to make incisions. The device consists of two or three main optical cables that carry light into the patient’s body and reflect that light back up to the physician’s eyepiece, which is then displayed on a television monitor.

Optical fibers are long, thin threads that allow transmitting of light signals over long distances. They have a core made of glass or plastic and a protective sheath that protects it from damage.

These fibers can be used to transmit infrared light as well, which could potentially be helpful for imaging fluorescent markers that emit at wavelengths outside the visible spectrum. Moreover, infrared light could be useful for imaging cells that are embedded more deeply within the tissue than can be imaged with visible wavelengths.

CCD and CMOS image sensors are integrated into the flexible endoscope lens assembly. Both devices capture spatial and intensity data that is readout by a charge to voltage converter.