NXlens_em

Status:

base class, extends NXobject

Description:

Description of an electro-magnetic lens or a compound lens.

For NXtransformations the origin of the coordinate system is placed in the center of the lens (its polepiece, pinhole, or another point of reference). The origin should be specified in the NXtransformations.

For details of electro-magnetic lenses in the literature see e.g. L. Reimer

Symbols:

No symbol table

Groups cited:

NXfabrication, NXtransformations

Structure:

type: (optional) NX_CHAR

Qualitative type of lens with respect to the number of pole pieces.

Any of these values:

  • single

  • double

  • quadrupole

  • hexapole

  • octupole

name: (optional) NX_CHAR

Given name, alias, colloquial, or short name for the lens. For manufacturer names and identifiers use respective manufacturer fields.

manufacturer_name: (optional) NX_CHAR

Name of the manufacturer who built/constructed the lens.

model: (optional) NX_CHAR

Hardware name, hash identifier, or serial number that was given by the manufacturer to identify the lens.

description: (optional) NX_CHAR

Ideally an identifier, persistent link, or free text which gives further details about the lens.

voltage: (optional) NX_NUMBER {units=NX_VOLTAGE}

Excitation voltage of the lens. For dipoles it is a single number. For higher orders, it is an array.

current: (optional) NX_NUMBER {units=NX_CURRENT}

Excitation current of the lens. For dipoles it is a single number. For higher orders, it is an array.

value: (optional) NX_NUMBER {units=NX_ANY}

This field should be used when the exact voltage or current of the lens is not directly controllable as the control software of the microscope does not enable users/or is was not configured to enable the user to retrieve these values. In this case this field should be used to specify the value as read from the control software. Although consumers of the application definition should not expect this value to represent the exact physical voltage or excitation, it is still useful to know though as it allows other users to reuse this lens setting, which, provided a properly working instrument and software should bring the lenses into a similar state.

depends_on: (optional) NX_CHAR

Specifies the position of the lens by pointing to the last transformation in the transformation chain in the NXtransformations group.

FABRICATION: (optional) NXfabrication

TRANSFORMATIONS: (optional) NXtransformations

Collection of axis-based translations and rotations to describe the location and geometry of the lens as a component in the instrument. Typically, the components of a system should all be related relative to each other and only one component should relate to the reference coordinate system.

Hypertext Anchors

List of hypertext anchors for all groups, fields, attributes, and links defined in this class.

NXDL Source:

https://github.com/FAIRmat-Experimental/nexus_definitions/tree/fairmat/contributed_definitions/NXlens_em.nxdl.xml