Viewed through a 40x lens, objects seem twice as big as with a 20x lens. It seems logical to think a higher magnification objective is “better”. But does it matter what it says on the tin?
In conventional light microscopy, the magnification of the objective lens is very straightforward: a 20x magnification means the image is magnified to a size 20 times larger than the original. Thus, when viewed with 40x magnification, objects seem twice as big as with a 20x lens. It’s logical that the pathologist wants a turret of objectives with a range of magnification to be able to get an overview of the sample, to examine it and to make an informed diagnosis. It also seems logical to think a higher magnification objective is “better”. But does it matter what it says on the tin?
In digital microscopy the magnification steps are achieved in a different manner. The slide is scanned, i.e. photographed in full resolution and the resulting image can be zoomed in and out to get the best scale view of the sample. The simplicity of the continuously variable magnification of a digital zoom makes moving between an overview and the desired level of detail incredibly easy. Digitally, any part of the image can also be magnified to a size far larger than it would ever appear through an eyepiece. A good overview camera and a single, high quality objective lens are thus enough to make an excellent digital microscope which is easy and fluent to use.
If you want to learn more about digital microscopy, read our whitepaper "Resolution and scanning speed in high-power digital microscopy" by our Principal Imaging Engineer Markus Vartiainen. The white paper discusses key principles of microscopy, focusing on resolution and scanning speed in digital scanning microscopy. It explains that magnification alone does not determine a microscope's resolving ability; numerical aperture (N.A.) is the critical factor.
The Grundium Ocus® delivers the highest quality images in digital pathology. The Ocus uses color stacking as one of the steps to achieve this. In conventional RGB imaging, the color channels are mapped in a single image, resulting in an approximation in assigning color value to each pixel. The Grundium Ocus takes full-resolution photos individually of each color, red, green, and blue, and the final image is automatically composed of these three layers. This process results in a sharp image with a far superior level of detail, as the starting point is three times more pixels than when using a conventional color sensor.
Where other scanners sweep the sample using a pre-defined focus map, the Grundium Ocus automatically focuses each field, putting the whole sample in focus without making time-consuming focus maps.
In summary, the Grundium Ocus is a combination of optimal magnification and optimal numerical aperture. It quickly produces a clear and sharp scanned image, which is excellent for digital pathology. The scanned images are effortless to view and zoom on a screen. The images or even remote operation of the Ocus scanner can be swiftly shared online. Ease of sharing means an expert, a group of students, a lecture audience, or a second opinion can be available just a couple clicks away.
Both of the Ocus® series microscope scanners are single slide whole slide scanners (WSI scanners) optimized for their specific tasks, but each masters a broad spectrum of pathology work. They look almost the same and boast the same excellent features: the small footprint, ease of use, superior connectivity, etc. – but the difference is in their comparable magnification levels.
The Ocus®20, with a comparable magnification of 20x, is optimized for fast and effortless scanning. Its perfect balance between image resolution and scan time makes it especially suitable for intraoperative frozen sections and histopathology.
The Ocus®40, with its comparable magnification of 40x, is designed to scan images at a high resolution, which makes it suitable for a wide range of applications, such as cytology.
