Confocal Microscope views structures in cells measuring 100 nm.

Press Release Summary:

TCS 4Pi confocal microscope utilizes microscopy technique that merges spherical waves of 2 objectives in such a manner that they result in single round sample. Unit records specimens in layers, resulting in 3D stacked images, which enables users to rotate image and view and measure it from all sides. Microscope is designed to explore dynamics and interaction of proteins within cells.

Original Press Release:

Leica Microsystems Presents the World's First 4Pi Confocal Microscope

Science Reaches for the Building Blocks of Life

The 4Pi microscope is the first fundamental improvement in the imaging quality of light microscopy in over 100 years, and Prof. Stefan Hell, director of the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany, made a significant contribution to this end. Together with Leica Microsystems, he developed a method with which structures in living cells measuring 100 nanometers can be depicted for the first time. As a result, it is now possible to better comprehend structures and processes within cells and thus explain the dynamics and interaction of proteins within a cell, for example. The life sciences will therefore be experiencing a boost in basic research in the near future. Dr. Thomas Zapf, Director of Scientific Relations, Leica Microsystems AG, anticipates progress in the development of treatments for protein related diseases such as diabetes and Alzheimer's as a result.

According to Leica Microsystems' CEO Dr. Wolf-Otto Reuter, innovations of this magnitude are not a matter of coincidence. They are a significant element of Leica's strategy and corporate culture and are the result of a systematic process: "Working with the user and for the user is the guiding principle behind our success in innovation. Every year, we launch over 20 new products. We realize 40 to 50 percent of our sales and over half of our margin with products that are no more than three years old.

With the new Leica TCS 4Pi confocal microscope, we're underscoring our innovative leadership in the high-end microscopy sector and are delivering the impetus for further development in our company," Reuter explained during the presentation of the new technology in Mannheim, Germany.

With 4Pi technology, the development team from Leica Microsystems and the Max Planck Institute succeeded in reducing the size of the focal light spot, thus increasing the sharpness of the image. In the late 19th century, Ernst Abbe recognized that due to its wave structure, light cannot be gathered to a point, but only to a "light spot". The size of the light spot depends essentially on the wavelength of the light and the angle of aperture of the objective. The smaller the light spot, the higher the resolution - the ability to distinguish two objects from one another.

While the light spot can have a width of 200 nm, it can never be less than 500 nm along the optical axis - the light's direction of travel. Those are the absolute minimum values. The focus therefore has roughly the shape of a rugby ball rather than a sphere. As a result, 3D images can be separated less effectively along the light's axis of travel and are strongly distorted in that direction.

The expansion of the focus along the optical axis has a simple physical cause: The purpose of the objective is to concentrate the light in the focal point. This is achieved by transforming the incoming two-dimensional light wave into a three-dimensional spherical wave aligned with the focal point. But as this spherical wave is not truly spherical, the light spot is elongated along its axis of travel.

With 4Pi technology, scientists of the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany, and Leica Microsystems have developed a fundamentally new microscopy technique and refined it into a mature application. In the project, which was sponsored by the German Ministry for Education and Research (BMBF), they merged the spherical waves of two objectives in such a manner that they resulted in a single, round one. This was realized by interference. This principle - the merger of two partial spherical waves to a whole - accounts for the name of the microscope, "4Pi", referring to the full solid angle of a genuine spherical wave.

The same principle can be applied to fluorescent light. The application of both at the same time - for the illumination of a point and the collection of light from the same point - results in a 3-7 fold increase in axial resolution, and thus a significant gain in sharpness. "Highest precision is required here," explained Dr. Thomas Zapf. "The length of the axes from the beam splitter to the joint focal plane of the objective pair must be identical, right down to fractions of a wavelength. This is necessary in order for the light waves to overlap at the focal point to achieve the significantly improved resolution."

The principle of confocal microscopy is to generate three-dimensional images of the highest resolution. Confocal - loosely translated as "with the focus" - refers to the visibility of only the optically sharp focal plane. Confocal technology eliminates all unsharp image information from other focal planes, with a reduced depth of field resulting in sharper images.

In order to view the complete three-dimensional microscopic image of a specimen, confocal microscopes record specimens in layers - much like computer tomography - and store these sharp images as a three-dimensional image stack in the memory of the computer. The result is an image with extreme depth of field that can be rotated in the computer, and which can be viewed and measured from all sides.

The new 4Pi technology goes well beyond previous resolution limits, opening new perspectives for the study of living cells. Microscopic structures can now be shown with a sharpness of detail and wealth of structural information previously unattainable in any other commercial fluorescence microscope system. "This additional information will put the scientific community in a position to expand and deepen its understanding of processes in living cells and cellular organelles in order to attain new knowledge of their structures and interactions," assured Zapf.

This is of major importance for all life sciences - for immunology, for example. It is now possible to study details of malfunctions in the exchange of information between living cells that were not visible previously. Such investigations can lead to important insights for the battle against disorders of the immune system such as HIV. Another example is the mitochondrial structure of the yeast cell. Changes there can be determined and analyzed for important findings related to diseases such as Alzheimer's.

"These examples show the enormous potential for progress and new insights that 4Pi technology can provide in basic research. It will lead to rapid advances in the development of effective treatments for many diseases," predicted Zapf.

Leica Microsystems is a leading global designer and producer of innovative high-tech precision optics systems for the analysis of microstructures. It is one of the market leaders in each of its five business areas: Microscopy, Imaging Systems, Specimen Preparation, Medical Equipment and Semiconductor Equipment. Leica Microsystems manufactures a broad range of products for numerous applications, which require microscopic visual presentation, measurement, analysis or electron-beam lithography. The company offers system solutions in the areas of life science, including biotechnology and medicine, as well as the science of raw materials, industrial quality assurance and the semiconductor industry. The company is represented in over 100 countries with 10 manufacturing facilities in 7 countries, sales and service organizations in 19 countries, an international network of dealers, 3,600 employees and a turnover of EUR 521 million. The international management is headquartered in Wetzlar, Germany.

Dr. Kirstin Henze
Tel.: +49(0)6441/29-2550
Fax: +49(0)6441/29-2527

Leica Microsystems AG
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