9. Contrast methods for Leica DM4000 B/DM4500 P/DM5000 B

Simple overview observations

Place the transmitted light specimen on the polarizer.

Turn the condenser head inward.

Focus through the condenser using a low- power magnifying lens, such as a 5x.

Although this method does not provide good im- aging performance; it does make it possible to view rows of specimen very quickly.

λ/4- and λ plate, quartz wedge

Depending on their design, λ/4 and λ plates are installed on the underside of the condenser or, for polarizing microscope, in the 8x condenser disk (the vibration direction γ runs: ) or they are inserted in the tube slot. An automatic, spring-mounted dust cover flap closes the tube slot.

For the IC/P analyzer, the λ plate can be activat- ed by turning it so that the mark "I" is facing up- wards.

When the plate is activated, the path difference is increased or reduced according to Fig. 68. The corresponding color changes can be used to determine the vibration direction γ according to the larger refractive index (i.e. refractive index nγ). (The quartz wedge (69.7) allows various color shifts on the polarizing microscope.)

Circular polarization

When the specimen stage is rotated, birefrin- gent specimens show 4 extinction positions. When a larger number of birefringent speci- mens are present, a few birefringent specimens always show up randomly in the extinction posi- tion. Circular polarization is used for simulta- neous interference color observation of all specimens:

Remove the specimen from the beam path or locate the blank position of the specimen.

Cross the polarizers precisely. The polarizers must be positioned exactly in the N – S/E – W direction. This means that the analyzer must either be set exactly at 90° or 0° of polariza- tion.

Fig. 68 Interference color with dependence on the path difference or on the thickness and color changes in the addi- tion and subtraction areas of the λ and λ/4 plates.

 

 

 

schwarz

 

 

 

 

lavendelgrau

 

Ordnung

 

200

graublau

 

 

lebhaftgelb

 

 

 

 

gelblichweiß

 

1.

 

λ

 

 

 

400

 

 

 

 

 

 

 

 

 

rotorange

λ

 

 

 

tiefrot

– –

 

 

600

indigo

4

 

 

 

himmelblau

λ

 

 

 

+ –

Ordnung3. 2. Ordnung

 

 

grünlichblau

4

 

800

 

Gangunterschied

hellgrün

 

+ λ

fleischfarben

 

 

 

reingelb

 

 

 

1000

orangerot

 

 

 

 

dunkelviolettrot

 

1200

indigo

grünlichblau

 

1400

meergrün

grünlichgelb

 

1600

kaminrot

mattpurpur

 

63

Page 63
Image 63
Leica DM5000B, DM4000M, DM4500P manual Simple overview observations, Λ plate, quartz wedge, Circular polarization

DM4500P, DM5000B, DM4000M specifications

The Leica DM4000M and DM4000B are state-of-the-art microscopes designed for professional use in the fields of biology, materials science, and clinical applications. Renowned for their precision and innovative features, these instruments are perfect for researchers and clinicians needing high-resolution imaging capabilities.

One of the standout features of both models is the advanced motorized focusing system, which allows for swift adjustments and precise control. This feature is particularly useful in time-sensitive research environments, where accuracy and speed are paramount. The ergonomically designed focus mechanism promotes user comfort during prolonged observation sessions.

Both the DM4000M and DM4000B incorporate the revolutionary Leica Application Suite (LAS) software. This intuitive platform is designed to maximize the functionality of the microscope, enabling users to capture, analyze, and share images seamlessly. The software’s integrated tools are perfect for documenting findings and enhancing research productivity.

Another notable characteristic of the DM4000 series is the modular design, which allows for easy customization and upgrading. This aspect ensures that users can tailor their microscopes to meet specific research needs, whether it be for fluorescence microscopy, phase contrast, or even special imaging techniques like HSR or IR.

The high-performance optics provide exceptional image contrast and clarity, allowing users to observe minute details in samples. The combination of high numerical aperture objectives and advanced optical coatings enhances the resolution, making the DM4000 series ideal for examining intricate biological specimens as well as materials with complex textures.

The DM4000B model is particularly suited for routine clinical applications, featuring specific tools designed for rapid diagnosis and efficient workflows. Its user-friendly interface and dedicated clinical applications streamline laboratory processes, making it an essential device in any clinical setting.

Additionally, both models are equipped with LED illumination, which offers consistent light intensity and color temperature. This feature improves sample clarity while reducing heat generation, thereby protecting sensitive specimens during prolonged observation periods.

In conclusion, the Leica DM4000M and DM4000B microscopes represent a blend of advanced technology, intuitive design, and high adaptability. Their user-focused features and exceptional optical performance make them indispensable tools for researchers and clinical professionals aiming for excellence in microscopy.