Light microscope having a sample stage for cryomicroscopy
In a light microscope ( 1 ) for cryomicroscopy, encompassing at least an objective ( 2 ) and a sample stage ( 3 ) having a cutout ( 7 ) for a coolable holder ( 8 ) for a sample carrier mount, the cutout ( 7 ) being covered by a cover ( 6 ), the sample stage ( 3 ) is displaceable in two horizontal directions ( 4 ). The cover ( 6 ) rests floatingly on the sample stage ( 3 ), and the objective ( 2 ) passes through a cutout ( 12 ), corresponding to the objective ( 2 ), in the cover ( 6 ). The method for cooling a holder ( 8 ) for a sample carrier mount in a light microscope ( 1 ) for cryomicroscopes, by means of a flow of liquid nitrogen through a cooling conduit ( 15 ), open at at least one end, in the holder ( 8 ), is notable for the fact that the quantity of liquid nitrogen is dimensioned so that all of the nitrogen is present in gaseous form at at least one open end ( 16 ) of the cooling conduit ( 15 ).
1. A light microscope ( 1 ) for cryomicroscopy, comprising an objective ( 2 ) and a sample stage ( 3 ) having a cutout ( 7 ) in which a coolable holder ( 8 ) for holding a sample carrier mount is located, the cutout ( 7 ) being covered by a cover ( 6 ),
wherein the sample stage ( 3 ) is displaceable in two horizontal directions ( 4 ); the cover ( 6 ) rests floatingly on the sample stage ( 3 ); and the objective ( 2 ) passes through a cutout ( 12 ) in the cover ( 6 );
wherein the holder ( 8 ) is operable to immobilize the sample carrier mount directly on the holder ( 8 ) and the holder ( 8 ) has a nitrogen internal cooling system; and
wherein the cover ( 6 ) comprises a double panel ( 6 ′) having a first panel spaced apart from a second panel by a gap for reducing condensation on the cover.
2. The light microscope according to claim 1 , wherein the cutout ( 12 ) in the cover ( 6 ) is a circular hole whose diameter is less than 2 mm larger than a diameter of a portion of the objective ( 2 ) which passes through the cutout ( 12 ) in the cover ( 6 ).
3. The light microscope according to claim 1 , wherein the sample stage ( 3 ) is coolable.
4. The light microscope according to claim 1 , wherein the sample stage ( 3 ) has an opening ( 5 ) for delivery of the sample carrier mount to the holder ( 8 ).
5. The light microscope according to claim 4 , further comprising a closure device ( 10 ) operable to close the opening ( 5 ).
6. The light microscope according to claim 1 , wherein the double panel ( 6 ′) is transparent.
7. A method for cooling the holder ( 8 ) for holding a sample carrier mount in the light microscope ( 1 ) for cryomicroscopy according to claim 6 , wherein the holder ( 8 ) is operable to immobilize the sample carrier mount directly on the holder ( 8 ), comprising:
providing a cooling conduit ( 15 ) in the holder ( 8 ), the cooling conduit ( 15 ) having at least one open end ( 16 ),
guiding a flow of liquid nitrogen through the cooling conduit ( 15 ) in the holder ( 8 ),
wherein the flow of liquid nitrogen is dimensioned so that all of the nitrogen is present in gaseous form at the at least one open end ( 16 ) of the cooling conduit ( 15 ).
8. The method according to claim 7 , wherein a metal frit element ( 17 ) is placed at the at least one open end ( 16 ) of the cooling conduit ( 15 ).