Beam Alignment, Eucentric Height Adjustment

2.13If the operator intends to expose TEM negatives using the built-in camera, it is best to ensure that the CCD camera is retracted and shut off so that it cannot interfere with the shutter mechanism. Using the Mac computer, whose CRT and keyboard rest on top on the CM-200 operating console, the operator may open Digital Micrograph (if it is not already open), select MSC from the top toolbar, and from that pull-down menu click to retract the CCD camera. The CCD camera control unit, which rests to the left of the Mac CRT, may also be turned off using the red switch on the front. Left.

3.Beam Alignment

These functions are performed without a specimen in the holder and may be performed without inserting a specimen holder at all. If a holder is not in place, a radiation safety interlock prevents the spot size from being changed to a number lower than 5 (the largest and brightest spot size is no. 1). This will produce a much dimmer beam image than that seen with the holder in place.

3.1Using the MAGNIFICATION knob, select 17,500x.

3.2Defocus the electron beam by turning the INTENSITY knob clockwise to strongly overfocus the C2 lens. Bring the beam back to crossover (the smallest image of the beam) and center it using the SHIFT X/Y knobs.

3.3Choose a C2 aperture (usually position 3, which is a 100-micron aperture) by rotating the largest knurled knob on the topmost aperture control on the column to the desired position.

3.4Using the INTENSITY knob, slowly overfocus (turn clockwise) the beam to coincide with the diameter of the intermediate-sized black circle on the phosphorescent viewing screen. If the defocused beam is not coincident with the circle, adjust it using the C2 aperture centering controls. These are both the intermediate-sized knurled knob on the aperture rod and the knurled knob on the side of the assembly (to the right). DO NOT TOUCH THE SMALLEST, INNERMOST KNOB BECAUSE IT UNSCREWS THE APERTURE ROD. Repeat these steps (3 and 5) until the beam spreads uniformly around the reference circle while being over focused (INTENSITY knob).

3.5Using the INTENSITY knob, adjust the beam to crossover. Depress the FINE button (to the left of the INTENSITY knob; the indicator light turns green when it is on) and use the INTENSITY knob to sharpen the de-saturated filament image. Center the image using the SHIFT X/Y knobs.

3.6Press the STIG button, on the right-hand instrument panel, to open the STIGMATOR CONTROL page.

3.7Press the COND key on the data monitor screen to select the C2 lens for astigmatism correction. Use the MULTIFUNCTION X/Y knobs, while rotating the beam through crossover using the INTENSITY knob, to obtain the cleanest, roundest de-saturated filament image possible.

3.8Press the STIG button to return to the CONFIGURATION page.

3.9Turn the FILAMENT knob clockwise to fully saturate the filament. When the saturation point (as defined by the FIL LIMIT) has been reached, the microscope will emit a 'beep.'

3.10Press the READY button and then the TEM key to return to TEM BRIGHTFIELD.

3.11Using the lever to the left of the viewing chamber, lower the small phosphorescent screen into place. Insert the beam stop (at the right-hand side top of the viewing chamber) so that it will be visible across the small screen. Use the binoculars to observe the beam stop. To adjust the binoculars for your eyes, first adjust the interpupillary distance so that you can see through them with both eyes; then adjust each eyepiece so that the rough edges of the beam stop are in focus for each eye. When you are done, retract the beam stop and lift the small screen back out of view.

4.Eucentric Height Adjustment

4.1Set the MAGNIFICATION to 5,800x and use the X/Y JOYSTICK to center a small notable feature of your specimen.

4.2Focus your chosen feature using the knobs marked STEP SIZE. The outer knob changes the focus; the inner knob (the step size adjustment) modifies the amount of focus change per 'click' of the outer knob.

CM-200 specifications

The Philips CM-200 is a sophisticated electron microscope designed to facilitate high-resolution imaging and analysis of materials at the nanoscale. Renowned for its robust performance and versatility, the CM-200 is utilized extensively in both research and industrial applications, particularly in materials science, biology, and nanotechnology.

One of the key features of the CM-200 is its advanced electron optics, which utilizes a high-tension generator to produce a stable and finely focused electron beam. This enables researchers to achieve magnifications of up to 1,000,000 times, allowing for the visualization of structures that are mere nanometers in size. The high resolution is further complemented by a large depth of field, which provides unprecedented clarity and detail in imaging complex samples.

The CM-200 also incorporates a range of imaging modes, including bright field, dark field, and selected area diffraction imaging. These modes allow for a comprehensive analysis of the sample under various conditions, making it easier to identify structural features and materials' properties. Furthermore, the microscope is equipped with a state-of-the-art camera system, which captures high-quality images and facilitates real-time observation.

In terms of sample preparation, the CM-200 supports various techniques, including ultra-thin sectioning and cryo-preparation methods. This flexibility makes it suitable for analyzing a wide array of sample types, from biological tissues to advanced material composites. The ability to handle both conductive and non-conductive samples without significant alteration ensures that the integrity of the sample is maintained throughout the imaging process.

Moreover, the CM-200 is designed with ease of use in mind. Its intuitive interface and automated functions streamline operation, allowing users to focus on analysis rather than technical adjustments. This user-friendly design promotes efficiency and accessibility for both novice and experienced researchers.

In summary, the Philips CM-200 is a cutting-edge electron microscope that combines advanced technologies with user-centric features. Its high-resolution imaging capabilities, versatile imaging modes, and adaptability for various sample types make it an invaluable tool in scientific research and industrial applications. Researchers can rely on the CM-200 to provide detailed insights into the nanoscale world, driving advancements across multiple fields.