Synopsis
The development of modern microscopy has brought many new techniques to medical practice. Microscopy is a field that is constantly evolving. Water- and oil-immersed lenses are two such inventions that have become very powerful tools in modern microscopy. These lenses are specifically designed to improve the quality of work. As the pathological needs grow, researchers are constantly trying to find new ways to make more powerful lenses for better diagnostics and research. If you’re wondering whether it’s better to use a water immersion lens or an oil immersion lens, the answer depends on your needs. You can use water immersion lenses to minimize the light loss in your work and oil immersion lenses to increase resolution. We’ll discuss the most important features of these lenses below.
New Microscopy Tools
With advances in microscopy technology, it has never been easier to study the world of cells, tissues and microorganisms in depth. Various techniques have emerged over the past few years, with the use of submersible lenses in water and oil being particularly popular. These lenses have become an indispensable tool for modern microscopy. Designed to optimize resolution and aberration, these lenses play a crucial role in revealing intricate details of small specimens that are imperceptible to the naked eye.
What Is the Technique Behind These Lenses?
Light travels through liquids differently due to the refractive index of the medium. Furthermore, different liquids produce different results. In addition to water and oil, other immersion media include ethyl cinnamate, TDE, mineral oil, silicone oil, and other organic media. However, these media do not work properly on standard lenses and instead require special objective lens corrections to properly utilize the effect. However, water and oil immersion work with standard lenses.
What Is an Immersion Lens?
Immersion lenses are a class of microscope objectives designed to overcome the limitations imposed by the wavelength of light and the numerical aperture (NA) of the lens. However, if there is a refractive index mismatch between air and glass slides, this can lead to light scattering and reduced resolution. To mitigate this issue, water and oil immersion lenses utilize the concept of optical matching by placing a medium with a higher refractive index between the objective lens and the sample.
Water Immersion Lens
Water immersion lenses use water as the immersion medium. The refractive index of water is closer to that of glass, which reduces light scattering and improves resolution. The refractive index of water (approx. n=1.33) is higher than that of air (approx. n=1.0), making water an ideal medium to minimize light loss as it passes through the sample.
How Does Water Immersion Lens Work?
A drop of water is placed on a specimen slide and a water immersion lens is carefully placed over the drop. This creates a continuous optical path where light travels from the sample through the water droplet to the lens without encountering air interfaces that may cause distortion or aberration. This results in a clearer, more detailed image, especially when looking at transparent or translucent samples such as living cells or uncontaminated materials.
Oil Immersion Lenses
An oil immersion lens uses a specialized immersion oil that has a refractive index close to that of glass. The oil is typically placed between the sample and the lens, thereby eliminating refractive index mismatch and further improving resolution and light-gathering capabilities.
How Does Oil Immersion Lens Work?
Immersion oil is placed directly on the sample on a slide and then the lens is carefully placed on the drop of oil. Close matching of refractive indices ensures that light loss due to refraction and reflection is minimized. Oil immersion lenses are particularly useful for obtaining the highest possible resolution and are commonly used in high-magnification microscopy techniques such as confocal microscopy and fluorescence microscopy.
Transformative Roles in Research and Precision Diagnostics
Water– and oil-immersion lenses have added value to research and diagnostics. They enable scientists and medical professionals to explore and diagnose with unprecedented precision. Such lenses allow you to work with high-magnification images with fine focus and a high NA.
Key Applications
- Cell biology: Immersion lenses are indispensable for observing complex intracellular structures and processes. From observing subcellular organelles to tracking cellular dynamics, immersion lenses provide the clarity and detail needed to understand cellular function. Oil immersion lenses are suitable for applications that require 100x or higher magnification.
- Histology: Oil immersion lenses play an important role in examining tissue samples for diagnosis. These lenses enable pathologists to recognize subtle cellular abnormalities that can help accurately diagnose disease.
- Microorganism Study: Microbiologists rely on immersion lenses to study microorganisms, including bacteria and fungi. The high resolution provided by these lenses helps identify species and analyze microbial behavior faster and more effectively.
- Neuroscience: Lenses immersed in water and oil are valuable for studying the complex neural networks and connections in the brain. These lenses help neuroscientists unravel the mysteries of brain structure and function.
- Material Science: Immersion lenses are not limited to biological samples. Materials science researchers use these lenses to analyze the microstructure of materials, facilitating the development of advanced materials with customized properties.
- Multi-photo Fluorescence Microscopy (MPFM): MPFM also uses water and oil immersion methods. It is an effective image resolution technique for exploring the mysteries of biological samples. Here, near-infrared wavelengths are used for multi-image excitation. This allows deeper penetration of optically turbid samples. Optical properties such as scattering coefficient and refractive index are usually heterogeneous.
High-quality Output
Lenses immersed in water and oil are one of the best examples of how innovative technology can reveal details and expand an expert’s understanding of microscopy. These lenses have changed the way cells, tissues, and microorganisms are explored. The PreciPoint O8 oil digital microscope and slide scanner represent a top solution for oil immersion, whole slide scanning, and oil microscopy. It uses oil and air lenses to scan entire slides and selected regions of interest. O8 can especially be used in hematology and oncology research.
Conclusion
In modern microscopy, water and oil immersion lenses are very valuable tools for achieving high-quality diagnostics or research results. Medical experts and researchers use them to overcome the limitations regarding wavelength and the numerical aperture of the lenses. In water immersion lenses, the light goes from the specimen through a continuous path without encountering air interfaces that could cause distortion or aberration. As a result, you get more sharp and more detailed images, especially important when you work with transparent or translucent specimens. In oil immersion lenses, the oil is typically placed between the specimen and the lens. Due to refraction and reflection, the light loss is minimal. Oil immersion lenses are especially useful for achieving the highest resolution possible and in high magnification microscopy techniques. Cell biology, histology, neuroscience, material science, and others are some of the main fields where water and oil microscopy are applied. PreciPoint’s O8 oil digital microscope scans entire slides and regions of interest in high resolution.
