4.3.1.57. NXxraylens

Status:

base class, extends NXobject

Description:

An X-ray lens, typically at a synchrotron X-ray beam line.

Based on information provided by Gerd Wellenreuther (DESY).

Symbols:

No symbol table

Groups cited:

NXnote, NXoff_geometry, NXtransformations

Structure:

@default: (optional) NX_CHAR

Declares which child group contains a path leading to a NXdata group.

It is recommended (as of NIAC2014) to use this attribute to help define the path to the default dataset to be plotted. See https://www.nexusformat.org/2014_How_to_find_default_data.html for a summary of the discussion.

lens_geometry: (optional) NX_CHAR

Geometry of the lens

Any of these values:

  • paraboloid

  • spherical

  • elliptical

  • hyperbolical

symmetric: (optional) NX_BOOLEAN

Is the device symmetric?

cylindrical: (optional) NX_BOOLEAN

Is the device cylindrical?

focus_type: (optional) NX_CHAR

The type of focus of the lens

Any of these values: line | point

lens_thickness: (optional) NX_FLOAT {units=NX_LENGTH}

Thickness of the lens

lens_length: (optional) NX_FLOAT {units=NX_LENGTH}

Length of the lens

curvature: (optional) NX_FLOAT {units=NX_LENGTH}

Radius of the curvature as measured in the middle of the lens

aperture: (optional) NX_FLOAT {units=NX_LENGTH}

Diameter of the lens.

number_of_lenses: (optional) NX_INT

Number of lenses that make up the compound lens.

lens_material: (optional) NX_CHAR

Material used to make the lens.

gas: (optional) NX_CHAR

Gas used to fill the lens

gas_pressure: (optional) NX_FLOAT {units=NX_PRESSURE}

Gas pressure in the lens

depends_on: (optional) NX_CHAR

NeXus positions components by applying a set of translations and rotations to apply to the component starting from 0, 0, 0. The order of these operations is critical and forms what NeXus calls a dependency chain. The depends_on field defines the path to the top most operation of the dependency chain or the string “.” if located in the origin. Usually these operations are stored in a NXtransformations group. But NeXus allows them to be stored anywhere.

cylinder_orientation: (optional) NXnote

Orientation of the cylinder axis.

OFF_GEOMETRY: (optional) NXoff_geometry

This group describes the shape of the beam line component

TRANSFORMATIONS: (optional) NXtransformations

This is the group recommended for holding the chain of translation and rotation operations necessary to position the component within the instrument. The dependency chain may however traverse similar groups in other component groups.

Hypertext Anchors

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

NXDL Source:

https://github.com/nexusformat/definitions/blob/main/base_classes/NXxraylens.nxdl.xml