5.Operation

5.5.2Freezing specimens onto specimen discs with 90 ° prism (Instruments w/specimen cooling only)

In instruments with specimen cooling, the 90 ° prism, which is inserted into the specimen head, is an additional option to freeze specimens at maximum temperature .

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Installing the 90 ° prism

Loosen screw (3) at specimen head.

Insert pin (1) of prism completely into recep- tacle (2) in the specimen head.

Important: the entire rear surface of the prism must fit tightly against the specimen head surface!

Retighten screw (3) at specimen head.

The prism now forms a horizontal surface for quick specimen freezing.

Freezing specimens with the 90 ° prism

Apply sufficient amount of embedding medi- um onto ambient temperature specimen disc, add specimen and orient.

Insert specimen disc with specimen into the receptacle (4) of the prism.

Press to activate menu item ‘Fast Object Freezing’ and activate function by pressing

(see chapter 5.3.4 ‘Menu functions’ item 4).

The specimen head is now automatically cooled down to the lowest temperature (-50 °C).

Once the specimen is frozen, remove the disc from the prism and store it in the quick- freeze shelf until inserting it into the speci- men head.

Press again to activate menu item ‘Fast Object Freezing’ and deactivate the function

by pressing once again (see chapter 5.3.4 ‘Menu functions’ item 4).

The specimen head temperature now automati- cally returns to the previously selected set val- ue.

Loosen screw (3) at specimen head and re- move prism (1).

Store prism inside the cryochamber.

5.5.3Optional accessories for freezing specimens onto specimen discs and for removing frozen specimens

Mobile heat extractor

In addition to the stationary heat extractor (part of standard delivery), a mobile heat extractor is available as an optional accessory - see Ap- pendix ‘Ordering information - accessories ):

Store heat extractor in chamber to precool.

Place onto specimen in quick-freeze shelf.

Remove as soon as specimen is frozen.

Leica CM 3050 S – Cryostat

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Leica CM3050 S instruction manual Installing the 90 prism, Freezing specimens with the 90 prism, Mobile heat extractor