Investigator for M4

17 min

This section covers the AMICS Investigator workflow for the Bruker M4 Tornado micro-XRF platform. While the general Investigator interface is shared with SEM, the M4 has significant differences in how specimens are loaded, data is collected, and results are processed.

Note: For SEM-specific workflows, see [Investigator for SEM].

M4 vs SEM — Key Differences

Aspect	SEM	M4 Tornado
Beam type	Electron beam	X-ray beam
Primary image	BSE (backscattered electron)	Camera image or Total Energy Intensity
Excitation	Accelerating voltage (kV)	X-ray tube voltage (kV) + current
Detectors	Single EDS detector	Up to 2 EDS detectors
Specimen stage	Motorized SEM stage	M4 motorized stage
Data format	MRE (native)	BCF (Bruker Common File) → MRE conversion
Spectral dispersion	Fixed (uniform energy/channel)	Variable (non-uniform energy spacing, new in 5.2.1)
Live imaging	Real-time BSE via SEM	Camera image via Esprit
Stage control	Full X/Y/Z/R via AMICS	Limited — controlled through M4 client

Loading a Specimen

Load Sample Dialog

When using the M4, the Load Sample dialog provides M4-specific controls:

{{FIG: M4 Load Sample dialog showing Open/Close shutter buttons and HV/Current controls | IDD_INVESTIGATOR_M4_LOAD_SAMPLE_DIALOG}}

Control	Description
Open	Open the M4 specimen chamber shutter
Close	Close the shutter
HV	High voltage (kV) — set or read the X-ray tube voltage
Current	Tube current — set or read the X-ray tube current
Read	Read current HV and current values from the M4
Set	Apply the entered HV and current values to the M4

Workflow

Physically load the specimen into the M4 chamber

Open the Load Sample dialog

Click Open to open the shutter

Set HV and Current to desired values (or click Read to get current values)

Click Set to apply

Close the dialog and proceed to measurement setup

M4 Settings

M4-specific settings are available in [Investigator Settings] under the M4/XRF section:

Setting	Description	Default
Default M4 KV	Default high tension (accelerating voltage)	Instrument default
Default M4 Current	Default probe current	Instrument default
Use Detector #1	Enable EDS Detector 1	On
Use Detector #2	Enable EDS Detector 2	On
X-Ray Collection Method	How x-rays are collected (see below)	Point by Point
Collect data on the fly	Collect x-ray data during stage movement	Off
# of retrying to collect M4 data	Retry attempts if collection fails	Default
Wait before retrying	Delay (ms) between retry attempts	Default
Lock M4 Client While Measuring	Prevent user interaction with M4 client during measurement	On
Active X-Ray Tube	Select which X-ray tube to use (systems with dual tubes)	Tube 1
Camera	Camera index for live view (0 or 1)	0
Online Logging to BCF	Log measurement data to BCF format in real time	Off
Auto-convert BCF	Automatically convert BCF to MRE after collection	Off
BCF File Folder	Folder for BCF logging. From 5.3.2, AMICS reads ESPRIT M4's data folder directly; when it is found, this setting is shown read-only. Otherwise set it to match the M4 client's folder	System default
API Mode Switch	Switch Esprit to API mode before measurement	Off

X-Ray Collection Methods

Method	Description
Point by Point	Collect x-rays at individual points sequentially (default, most reliable)
Line by Line	Collect along scan lines for faster acquisition
Line Direct	Direct line collection mode for maximum speed

Tip: Start with Point by Point for reliability. Switch to Line by Line or Line Direct for production throughput once you've verified your settings produce good results.

Measurement Modes on M4

The M4 supports most AMICS measurement modes, but with some differences:

Mode	M4 Support	Notes
Matrix Mapping	Full	Primary mode for M4 — x-rays collected on a regular grid
HyperMap	Full	Full hyperspectral mapping
Segmentation Mapping	Limited	Requires camera image or Total Energy Intensity for segmentation
Rare Phase Search	Limited	BSE-based search not available; use elemental scan filter
Image Mosaic	Camera-based	Uses M4 camera, not BSE

Matrix Mapping on M4

Matrix Mapping is the most common mode for M4:

Open the [Data Collection Wizard] or measurement settings

On the X-Ray tab, select Matrix mode

Set X Spacing and Y Spacing (µm) for the grid

Set Dwell Time or Counts for collection per point

Configure excitation: Voltage and Current

HyperMap on M4

For full hyperspectral data:

Select Hypermap mode in the X-Ray tab

Configure dwell time per pixel

Data is collected as a complete 2D spectral array (BCF format) at every grid position

Post-processing uses [Hypermap Segmentation] for spectral-distance-based segmentation

Linescan Mode

The M4 supports a Linescan mode for 1D compositional transects:

Extracts the center horizontal line from the measurement rectangle

Performs hypermap collection along the line only

Useful for compositional gradients, diffusion profiles, or elemental transects across grain boundaries

BCF Data and Conversion

M4 data is stored in Bruker's BCF (Bruker Common File) format. AMICS can work with BCF data in two ways:

Online BCF Logging

During measurement, AMICS can log data to BCF format in real time:

Enable Online Logging to BCF in M4 settings

Check the BCF File Folder — from 5.3.2 it is read from ESPRIT automatically when available; otherwise it must match the M4 client's BCF folder

Optionally enable Auto-convert BCF to automatically convert to MRE after measurement

BCF Import and Conversion

To import existing BCF files:

Open the BCF file in Process (or use Batch Convert BCF Files)

AMICS shows the BCF File Info dialog with:

File path and size

Image location and size

Pixel size and channel count

Detector count

High voltage

Quantification status and elements

{{FIG: BCF File Info dialog showing file metadata and Convert button | BCF File Info dialog}}

Click Convert to create an MRE file from the BCF data

Auto-Detect SEM vs M4 (New in 5.2.1)

AMICS 5.2.1 automatically detects whether a BCF file originates from an SEM or M4 system. This determines:

Default conversion settings

Whether Total Energy Intensity image generation is needed

Spectral dispersion handling

You no longer need to manually select the instrument type during import.

Variable Dispersion (New in 5.2.1)

M4 XRF data can have variable dispersion — the energy per channel is not uniform across the spectrum. AMICS 5.2.1 handles this automatically:

Variable dispersion metadata is read from the BCF file

Spectral matching accounts for non-uniform channel spacing

Element energy line positions are correctly mapped

This is particularly important when matching M4 data against reference libraries collected on instruments with different dispersion characteristics.

Legacy XRF Matching (New in 5.2.1)

If your reference spectra library was collected at 20 keV excitation:

Enable Match as 20 keV in the reclassification dialog (or batch settings)

AMICS temporarily resamples spectra to 20 keV format for matching

Original data is unchanged

Use the 20keV Ref toggle on the ribbon to verify reference overlay alignment

See [Legacy XRF Matching] for full documentation.

Elemental Visualization on M4

[Elemental Visualization] is particularly valuable for M4 data, as element maps are the primary analytical product:

M4 HyperMap data provides element intensity at every pixel

The elemental overlay shows spatial distribution of selected elements

Use Raw counts for quick visualization, Net counts for quantitative work

Element maps can be exported as images for reporting

Tip: For M4 data, Elemental Visualization combined with [Hypermap Segmentation] provides the most informative analysis — segmentation groups spectrally similar regions, and elemental visualization shows the chemistry.

Esprit Integration

AMICS communicates with the M4 through the Bruker Esprit software:

Esprit must be running for M4 measurement control

Quantification recipes are loaded from Esprit

The API Mode Switch setting forces Esprit into API mode before measurement (enable if AMICS cannot control the M4)

Hold Hardware Connection (set in the Tool's configuration) keeps the connection to Esprit open between operations. From 5.3.2 this setting, and Reset the Connection Error, are remembered between sessions instead of reverting to their defaults. On M4 we recommend keeping Hold Hardware Connection off, which avoids a crash in the Read HW Data → Survey → Start sequence

Esprit 3.0 with client 2.7 DLL is supported in AMICS 5.2.1

xCore systems use Esprit for live image display (20 keV x-ray limit)

Robust HyMap Check (New in 5.2.1)

AMICS 5.2.1 includes improved validation of M4 HyperMap data integrity, detecting and handling incomplete or corrupted HyperMap acquisitions more gracefully.

Tips for M4 Users

Use Matrix Mapping as your default mode — it's the most natural fit for M4 grid-based collection

Enable both detectors (#1 and #2) for maximum count rate

Set Lock M4 Client to On during measurement to prevent accidental interference

Use Online BCF Logging to keep a BCF archive alongside MRE results

The Global Materials Library has M4-specific entries — filter by "M4" when inserting materials

For large area maps, use [MIST Stitching] to align fields after collection