Device and method for feeding an immersion medium

Patent metadata

Field	Value
Publication number	US-11216017-B2
Application number	US-202016835449-A
Country	US
Kind code	B2
Filing date	Mar 31, 2020
Priority date	Apr 2, 2019
Publication date	Jan 4, 2022
Grant date	Jan 4, 2022

Abstract

A feed device for an immersion medium for use with an objective enabling a specimen to be imaged microscopically includes a cap fitted releasably or fixedly to the objective and delimiting a receptacle space for the immersion medium. The cap has an exit opening aligned with an optical element of the objective facing the specimen. The immersion medium held in the receptacle space is feedable through the exit opening to a target space situated between the optical element of the objective and the specimen. A sensor is integrated in the cap and has an electrode structure configured to detect an amount of the immersion medium fed through the exit opening to the target space. The electrode structure at least partly encloses the exit opening and has a spatial detection region extending away from the exit opening in a radial direction.

First claim

What is claimed is:

1. A feed device for an immersion medium for use with an objective enabling a specimen to be imaged microscopically, the feed device comprising:
a cap fitted releasably or fixedly to the objective and delimiting a receptacle space for the immersion medium, the cap having an exit opening aligned with an optical element of the objective facing the specimen, the immersion medium held in the receptacle space being feedable through the exit opening to a target space situated between the optical element of the objective and the specimen, and
a sensor integrated in the cap and having an electrode structure configured to detect an amount of the immersion medium fed through the exit opening to the target space, the electrode structure at least partly enclosing the exit opening and having a spatial detection region extending away from the exit opening in a radial direction.

2. The feed device as claimed in claim 1 , wherein the sensor is a capacitive or resistive sensor.

3. The feed device as claimed in claim 1 , wherein the electrode structure of the sensor is insensitive to an amount of the immersion medium situated in the exit opening.

4. The feed device as claimed in claim 1 , wherein the electrode structure of the sensor is sensitive to an amount of the immersion medium situated in the exit opening.

5. The feed device as claimed in claim 1 , wherein the electrode structure is embodied as an interdigitated structure.

6. The feed device as claimed in claim 1 , wherein the exit opening is circular and the electrode structure is embodied rotationally symmetrically with respect to the exit opening.

7. The feed device as claimed in claim 1 , wherein the electrode structure has a plurality of mutually independently drivable electrode pairs distributed around the exit opening.

8. The feed device as claimed in claim 1 , further comprising a measuring unit for the sensor, the measuring unit being integrated into the cap.

9. The feed device as claimed in claim 1 , wherein an edge of an end wall of the cap delimiting the exit opening, together with the optical element of the objective, forms a gap through which the immersion medium emerges into the target space.

10. The feed device as claimed in claim 1 , wherein an end wall of the cap extends substantially conically toward the exit opening.

11. The feed device as claimed in claim 1 , wherein the cap has a substantially cylindrical wall adjacent to an end wall of the cap, the cylindrical wall together with the end wall delimiting the receptacle space for the immersion medium.

12. An objective comprising the feed device as claimed in claim 1 .

13. The feed device as claimed in claim 1 , wherein the cap has an end wall facing the specimen, the exit opening being formed in the end wall, wherein the end wall separates the receptacle space from the target space and wherein the electrode structure is integrated into the end wall.

14. The feed device as claimed in claim 13 , wherein the end wall has a first material layer, which electrically insulates the electrode structure of the sensor from the receptacle space, and a second material layer, which electrically insulates the electrode structure of the sensor from the target space.

15. The feed device as claimed in claim 13 , wherein the end wall electrically insulates the electrode structure of the sensor firstly from the receptacle space and secondly from the target space in such a way that the spatial detection region of the electrode structure covers at least the entire target space.

16. The feed device as claimed in claim 15 , wherein the spatial detection region of the electrode structure also covers the receptacle space.

17. The feed device as claimed in claim 1 , further comprising a conductor track structure integrated in the cap, the conductor track structure being electrically insulated from the receptacle space and the target space and being configured to resistively heat the immersion medium.

18. The feed device as claimed in claim 17 , wherein the conductor track structure follows a winding course.

19. The feed device as claimed in claim 17 , further comprising a temperature sensor configured to detect a temperature of the immersion medium.

20. The feed device as claimed in claim 19 , wherein the temperature sensor is formed by the conductor track structure, which has a predetermined, temperature-dependent electrical resistance and is configured, alternately over time, to resistively heat the immersion medium held in the receptacle space and to resistively detect the temperature of the immersion medium.

21. The feed device as claimed in claim 1 , further comprising a pump system, which is connected to the receptacle space of the cap via at least one tube and is configured to pump the immersion medium into the receptacle space.

22. The feed device as claimed in claim 21 , further comprising an open-loop/closed-loop control unit configured to pump the immersion medium into the receptacle space depending on a detection signal supplied by the sensor.

23. A method for feeding an immersion medium using the feed device as claimed in claim 22 , the method comprising:
pumping the immersion medium into the receptacle space by the pump system;
simultaneously generating, by the sensor, a detection signal corresponding to the amount of the immersion medium fed through the exit opening to the target space; and
controlling the pump system to set a target amount of the immersion medium based on the detection signal.

24. The method as claimed in claim 23 , wherein the immersion medium is pumped into the receptacle space at a constant pump rate.

25. The method as claimed in claim 23 , wherein, for defining the target amount of the immersion medium, firstly an amount for which the immersion medium reaches the exit opening of the cap is detected as a reference amount of the immersion medium and then the target amount of the immersion medium is determined based on the reference amount of the immersion medium.

26. The method as claimed in claim 23 , wherein the target amount of the immersion medium is kept constant using a closed-loop control circuit.

27. The method as claimed in claim 26 , wherein the closed-loop control of the amount of immersion medium fed through the exit opening to the target space is suspended within a predetermined tolerance range around the target amount of the immersion medium and/or when a predetermined operating state is present.

Assignees

• Leica Microsystems

Inventors

• Weiss Alexander
• Hitzler Sebastian
• Schumann Christian

Classifications

• G01N27/226

  Construction of measuring vessels; Electrodes therefor · CPC title

• G01F23/263 Primary

  by measuring variations in capacitance of capacitors · CPC title

• G02B21/02

  Objectives · CPC title

• G02B21/33

  Immersion oils {, or microscope systems or objectives for use with immersion fluids} · CPC title

• G02B21/24

  Base structure · CPC title