Enhancing a Miniaturized Endoscopic Objective Lens
The application of endomicroscopes in various biomedical fields such as neuroscience and cancer detection and treatment especially of inner, hardly accessible organs demands the smallest possible diameters in combination with a large numerical aperture (NA) and field-of-view (FOV).
Here are some excerpts from the Introduction to the paper, entitled “Field curvature reduction in miniaturized high numerical aperture and large field-of-view objective lenses with sub 1 µm lateral resolution.”
In the scope of this research the miniaturized objective lens type MO-080-032-ACR-VISNIR-08CG-20 of the company GRINTECH was further developed and tailored to new applications. This state-of-the-art objective lens fulfils the criteria of a large NA of 0.73, a well-corrected FOV diameter of 264 µm as well as a design spectral range of at least 488 nm to 550 nm. This lens is currently used for endomicroscopic applications.
The first part of this paper sets the requirements for a novel device for new applications. Afterwards, the results of the design process are shown where three different design options are compared. In the last part of the paper, the assembled prototypes are evaluated regarding their performance by means of a confocal laser-scanning-microscope. Besides the resolution also the field curvature and the chromatic performance of the miniaturized objective lens are shown. Furthermore, biological cell samples were imaged with the device.
About GRINTECH
GRINTECH is a leading manufacturer of GRadient INdex (GRIN) micro-optic lenses and lens systems. These miniaturized lenses provide extraordinarily good optical performance and flat optical surfaces. (See the Explanation of the physics of GRIN lenses.)
The optical power of GRIN lenses is achieved by a refractive index profile fabricated in glass by a non-toxic, silver-and-lithium-ion-exchange process. These unique rod and cylindrical micro-lenses have typical diameters from 200 µm to 2 mm.
The GRINTECH catalog includes:
- GRIN rods used for fiber and laser diode collimation and beam shaping
- Lenses and assemblies for clinical and industrial endoscopic applications
- Needle imaging assemblies and miniature high-NA objectives for in-vivo endomicroscopy and related accessories
These products are used for medical imaging and biophotonic technology, optical metrology, and sensor technology for applications such as brain imaging and endomicroscopy. In addition, GRINTECH develops, fabricates, and delivers high quality, reliable, custom-made modules and assemblies, tailored to the specific needs of customer applications. These assemblies and subassemblies are often inspired by or based on GRINTECH’s standard products.
To support industrial customers, GRINTECH’s team of optical designers and mechanical engineers design and produce more complex optical sensors, focusing or deflecting modules, imaging assemblies consisting of mechanical housings and mounts, optical fibers, prisms, beam splitters, laser diodes, etc., which are combined with GRIN and other lenses.
Customizations include: fiber type, length, buffer, connector type, prism size, stainless steel tube mounts, angled fiber end face, coatings, design wavelengths, spot or image working distance, spot size and numerical aperture, etc.
For more information or a quotation for GRINTECH products, contact IL Photonics.