3.3.1.121. NXoptical_window

Status:

base class, extends NXaperture

Description:

A window of a cryostat, heater, vacuum chamber or a simple glass slide. ...

A window of a cryostat, heater, vacuum chamber or a simple glass slide.

This describes cryostat windows and other possible influences for ellipsometry measurements.

For environmental measurements, the environment (liquid, vapor etc.) is enclosed in a cell, which has windows both in the direction of the source (entry window) and the detector (exit window) (looking from the sample).

The windows also add a phase shift to the light altering the measured signal. This shift has to be corrected based on measuring a known sample (reference sample) or the actual sample of interest in the environmental cell. State if a window correction has been performed in ‘window_effects_corrected’. Reference measurements should be considered as a separate experiment (with a separate NeXus file), and the reference data shall be linked in reference_data_link.

The window is considered to be a part of the sample stage but also beam path. Hence, its position within the beam path should be defined by the ‘depends_on’ field.

Symbols:

No symbol table

Groups cited:

NXprocess

Structure:

window_effects_corrected: (optional) NX_BOOLEAN

Was a window correction performed? If so, describe the window ...

Was a window correction performed? If so, describe the window correction procedure in window_correction/procedure.

window_effects_type: (optional) NX_CHAR

Type of effects due to this window on the measurement. ...

Type of effects due to this window on the measurement.

Any of these values or a custom value (if you use a custom value, also set @custom=True):

  • interference effects

  • light absorption

  • light scattering

  • other

window_correction: (optional) NXprocess

Group to describe any window correction - if none performed, then omit this

procedure: (optional) NX_CHAR

Describe when (before or after the main measurement + time ...

Describe when (before or after the main measurement + time stamp in ‘date’) and how the window effects have been corrected, i.e. either mathematically or by performing a reference measurement. In the latter case, provide the link to to the reference data in reference_data_file.

reference_data_link: (optional) NX_NUMBER

:ref:`External link ` to the data field in the NeXus file whic ...

External link to the data field in the NeXus file which describes the reference data if a reference measurement for window correction was performed.

Ideally, the reference measurement was performed on the same sample, using the same conditions as for the actual measurement, with and, if possible, without windows. It should have been conducted as close in time to the actual measurement as possible.

Ideally, the link uses the relative path with respect to the actual NeXus file.

material: (optional) NX_CHAR ⤆

The material of the window. ...

The material of the window.

Any of these values or a custom value (if you use a custom value, also set @custom=True):

  • quartz

  • diamond

  • calcium fluoride

  • zinc selenide

  • thallium bromoiodide

  • alkali halide compound

  • Mylar

  • other

material_other: (optional) NX_CHAR

If you specified ‘other’ as material, describe here what it is.

thickness: (optional) NX_FLOAT {units=NX_LENGTH}

Thickness of the window.

orientation_angle: (optional) NX_FLOAT {units=NX_ANGLE}

Angle of the window normal (outer) vs. the substrate normal ...

Angle of the window normal (outer) vs. the substrate normal (similar to the angle of incidence).

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/NXoptical_window.nxdl.xml