Laser

`pychilaslasers.laser`

Define the Laser class for Chilas lasers.

This acts as the main interface for controlling the laser. Some properties and methods of the laser are accessible at all times, while others are only available in specific operation modes.

The modes of the laser are:

ManualMode: Allows manual control of the heater values.
TuneMode: Can be used to tune the laser to specific wavelengths according to the calibration data.
SweepMode: Sweep mode is used for COMET lasers to enable the sweep functionality.

Changing the diode current or TEC temperature of the laser is available in all modes however this implies that the calibration of the laser is no longer valid and the laser may not achieve the desired wavelength.

Authors: RLK, AVR, SDU

`pychilaslasers.Laser(com_port: str, calibration_file: str | Path | None = None)`

Laser class for Chilas lasers.

Contains the main methods for communication with the laser, the logic for changing and accessing the laser modes, and the properties of the laser. Multiple overloaded methods are available to interact with the laser. Many of the methods are overloads of other methods that either provide different ways do the same operation for convenience.

Usage

Accessing functionality of a specific mode is done through the mode property such as laser.tune.method_name() or laser.sweep.method_name(). This will however only work if the laser is in the correct mode. If the laser is not in the correct mode, an exception will be raised. The current mode of the laser can be set using the mode property as well.

The laser can be turned on and off using the system_state property. The laser can also be triggered to pulse using the trigger_pulse() method. The laser can be set to prefix mode using the prefix_mode property. The prefix mode can be used to speed up communication with the laser by reducing the amount of data sent over the serial connection however this reduces the amount of information that is sent back from the laser.

Some laser components such as the TEC and Diode can be accessed in all modes using the tec and diode properties respectively. Other components are only available in manual mode.

Attributes:

system (System) –

Container for system-wide non-functional attributes of the laser.
tec (TEC) –

The TEC component of the laser.
cpu (CPU) –

The temperature sensor in the CPU of the laser module.
pd1 (PhotoDiode) –

PhotoDiode 1 of laser. (Channel 0)
pd2 (PhotoDiode) –

PhotoDiode 2 of laser. (Channel 1)
enclosure (EnclosureTemp) –

Temperature sensor of laser module enclosure.
diode (Diode) –

The Diode component of the laser.
mode (Mode) –

The current mode of the laser.
system_state (bool) –

The system state of the laser (on/off).
prefix_mode (bool) –

Whether the laser is in prefix mode or not.

Opens the serial connection to the laser, initializes the laser components and variables, and sets the initial mode to manual.

Warning

During the initialization, the laser will turn on and communicate over the serial connection to gather necessary information about the laser and its components such as maximum values for parameters.

Parameters:

com_port (str) –

The COM port to which the laser is connected. This should be a string such as "COM7". To see available COM you may use the pychilaslasers.comm.list_comports method from the comm module.
calibration_file (str | Path, default: None ) –

The path to the calibration file that was provided for the laser.

Referenced by:

Used by:

Package Reference
- Laser Components
  - Heaters heaters Classes
    - Heater
    - PhaseSection Functions
      - calibrate
      - get_antihyst_method
  - Index laser_components Classes
- Modes modes Classes
System System

Source code in src/pychilaslasers/laser.py

def __init__(
    self, com_port: str, calibration_file: str | Path | None = None
) -> None:
    """Initialize the laser with the given COM port and calibration file.

    Opens the serial connection to the laser, initializes the laser components and
    variables, and sets the initial mode to manual.

    Warning:
        During the initialization, **the laser will turn on** and communicate over
        the serial connection to gather necessary information about the laser and
        its components such as maximum values for parameters.

    Args:
        com_port: The COM port to which the laser is connected. This should
            be a string such as "COM7". To see available COM you may use the
            `pychilaslasers.comm.list_comports` method from the `comm` module.
        calibration_file (str | Path):
            The path to the calibration file that was provided for the laser.

    """
    self._comm: Communication = Communication(com_port=com_port)
    self._system = System(self)

    try:
        # Laser identification. Library will not work with non-Chilas lasers.
        if (
            "Chilas" not in (idn := self._comm.query("*IDN?"))
            and "LioniX" not in idn
        ):
            logger.critical("Laser is not a Chilas device")
            import sys

            sys.exit(1)

        # Initialize laser components
        self.tec: TEC = TEC(self)
        self.diode: Diode = Diode(self)
        self.enclosure: EnclosureTemp = EnclosureTemp(self)
        self.cpu: CPU = CPU(self)
        self.pd1: PhotoDiode = PhotoDiode(self, 0)
        self.pd2: PhotoDiode = PhotoDiode(self, 1)

        # Initialize modes
        self._manual_mode: ManualMode = ManualMode(self)

        self._model: str = "Unknown"
        self._calibration: Calibration | None = None
        self._tune_mode: TuneMode | None = None
        self._sweep_mode: SweepMode | None = None

        if calibration_file is not None:
            self.calibrate(calibration_file=calibration_file)

        self._mode: Mode = self._manual_mode

        logger.debug(
            f"Initialized laser {self._model} on {com_port} with calibration file "
            f"{calibration_file}"
        )
    except Exception as e:
        self._comm.close_connection()
        raise e

Attributes

`comm: Communication` `property`

Communication object for the laser.

This property provides access to the communication object used to interact with the laser. It can be used to send commands and queries to the laser.

Returns:

Communication –

The communication object for the laser.

`system_state: bool` `property` `writable`

System state of the laser.

The property of the laser that indicates whether the laser is on or off. This is a boolean property that can be set to True to turn on the laser or False to turn it off.

Returns:

bool –

The system state. Whether the laser is on (True) or off (False).

`mode: LaserMode` `property` `writable`

Gets the current mode of the laser.

Returns:

LaserMode –

The current mode of the laser. This can be one of the following: - LaserMode.MANUAL - LaserMode.TUNE - LaserMode.SWEEP

`tune: TuneMode` `property`

Getter function for the tune mode instance.

This property allows access to the tune mode instance of the laser in a convenient way such as laser.tune.method(). Tune mode uses calibration data to tune the laser to specific wavelengths with high precision. This mode is available for both COMET and ATLAS lasers and provides wavelength control based on the laser's calibration file.

Warning

This method will not change the mode of the laser, it will only return the tune mode instance if the laser is in that mode. To switch to tune mode, use laser.mode = LaserMode.TUNE or laser.set_mode("tune") first.

Returns:

TuneMode –

The tune mode instance with access to wavelength control methods.

Raises:

ModeError –

If the laser is not in tune mode.

Example

>>> laser.mode = LaserMode.TUNE
>>> laser.tune.set_wavelength(1550.0)  # Set wavelength to 1550nm

`sweep: SweepMode` `property`

Getter function for the sweep mode instance.

This property allows access to the sweep mode instance of the laser in a convenient way such as laser.sweep.method(). Sweep mode is only available for COMET lasers and enables sweeping functionality for wavelength scanning applications. This mode uses calibration data to perform controlled wavelength sweeps across specified ranges.

Warning

This method will not change the mode of the laser, it will only return the sweep mode instance if the laser is in that mode. To switch to sweep mode, use laser.mode = LaserMode.SWEEP or laser.set_mode("sweep") first.

Returns:

SweepMode –

The sweep mode instance with access to sweep control methods.

Raises:

ModeError –

If the laser is not in sweep mode or sweep mode is not available.

Example

>>> laser.mode = LaserMode.SWEEP  # Only works for COMET lasers
>>> laser.sweep.start_wavelength_sweep(1550.0, 1560.0)  # Sweep from 1550nm to 1560nm

`manual: ManualMode` `property`

Getter function for the manual mode instance.

This property allows access to the manual mode instance of the laser in a convenient way such as laser.manual.method(). Manual mode is always available and is the default mode. In manual mode, you have direct control over individual laser components and can manually set heater values and other parameters.

Warning

This method will not change the mode of the laser, it will only return the manual mode instance if the laser is in that mode. To switch to manual mode, use laser.mode = LaserMode.MANUAL or laser.set_mode("manual") first.

Returns:

ManualMode –

The manual mode instance with access to manual control methods.

Raises:

ModeError –

If the laser is not in manual mode.

Example

>>> laser.mode = LaserMode.MANUAL
>>> laser.manual.set_heater_value(50.0)  # Set heater to 50%

`model: str` `property`

Return the model of the laser.

Returns:

str –

The model of the laser. May be "COMET" or "ATLAS"

`calibrated: bool` `property`

Check if the laser is calibrated.

Returns:

bool –

True if the laser has calibration data, False otherwise.

`calibration: Calibration | None` `property` `writable`

Get the current calibration object.

Returns:

Calibration | None –

Calibration | None: The current calibration object if available, None otherwise.

`system: System` `property`

Container for some informational attributes of the laser.

Functions

`trigger_pulse() -> None`

Instructs the laser to send a trigger pulse.

Source code in src/pychilaslasers/laser.py

def trigger_pulse(self) -> None:
    """Instructs the laser to send a trigger pulse."""
    self._comm.query(f"DRV:CYC:TRIG {int(True):d}")
    self._comm.query(f"DRV:CYC:TRIG {int(False):d}")

`calibrate(calibration_file: str | Path | None = None, calibration_object: Calibration | None = None) -> None`

Calibrates the laser with the given calibration file or calibration object.

This method configures the laser with calibration data, enabling tune mode and sweep mode (for COMET lasers). Exactly one of calibration_file or calibration_object must be provided.

Parameters:

calibration_file (str | Path | None, default: None ) –

The path to the calibration file to be used for calibrating the laser. Defaults to None.
calibration_object (Calibration | None, default: None ) –

A preloaded calibration object to be used for calibrating the laser. Defaults to None.

Raises:

KeyError –

If both calibration_file and calibration_object are provided, or if neither is provided.

Referenced by:

PyChilasLasers Quickstart Guide Initialization

Source code in src/pychilaslasers/laser.py

def calibrate(
    self,
    calibration_file: str | Path | None = None,
    calibration_object: Calibration | None = None,
) -> None:
    """Calibrates the laser with the given calibration file or calibration object.

    This method configures the laser with calibration data, enabling tune mode and
    sweep mode (for COMET lasers). Exactly one of calibration_file or
    calibration_object must be provided.

    Args:
        calibration_file (str | Path | None, optional):
            The path to the calibration file to be used for calibrating the laser.
            Defaults to None.
        calibration_object (Calibration | None, optional):
            A preloaded calibration object to be used for calibrating the laser.
            Defaults to None.

    Raises:
        KeyError: If both calibration_file and calibration_object are provided,
            or if neither is provided.
    """
    if not (calibration_file is None) ^ (calibration_object is None):
        raise KeyError(
            "Calibration file or object need to be provided for calibration "
            "but not at the same time."
        )

    calibration: Calibration
    if calibration_object is None:
        assert calibration_file is not None  # Type guard
        calibration = load_calibration(file_path=calibration_file)
    else:
        calibration = calibration_object

    # Laser attributes
    if (
        no := calibration.serial_number
    ) is not None and no != self.system.serial_no:
        logging.getLogger(__name__).critical(
            "Calibration file is for a different laser."
            + f"Calibration file serial number = {no} "
            + f"Laser serial number = {self.system.serial_no}"
        )
    self._calibration = calibration
    self._model = calibration.model
    self._manual_mode.phase_section.calibrate(calibration=calibration, laser=self)

    # Laser modes setup
    self._tune_mode = TuneMode(self, calibration)
    if self._model == "COMET":
        self._sweep_mode = SweepMode(self, calibration)

`set_mode(mode: LaserMode | Mode | str) -> None`

Set the mode of the laser.

This is an alias for the mode property setter.

Source code in src/pychilaslasers/laser.py

def set_mode(self, mode: LaserMode | Mode | str) -> None:
    """Set the mode of the laser.

    This is an alias for the `mode` property setter.
    """
    self.mode = mode

`turn_on() -> None`

Turn on the laser.

This is an alias for setting the system state to True.

Source code in src/pychilaslasers/laser.py

def turn_on(self) -> None:
    """Turn on the laser.

    This is an alias for setting the system state to True.
    """
    self.system_state = True

`turn_off() -> None`

Turn off the laser.

This is an alias for setting the system state to False.

Source code in src/pychilaslasers/laser.py

def turn_off(self) -> None:
    """Turn off the laser.

    This is an alias for setting the system state to False.
    """
    self.system_state = False

Laser

pychilaslasers.laser

pychilaslasers.Laser(com_port: str, calibration_file: str | Path | None = None)

Attributes

comm: Communication property

system_state: bool property writable

mode: LaserMode property writable

tune: TuneMode property

sweep: SweepMode property

manual: ManualMode property

model: str property

calibrated: bool property

calibration: Calibration | None property writable

system: System property

Functions

trigger_pulse() -> None

calibrate(calibration_file: str | Path | None = None, calibration_object: Calibration | None = None) -> None

set_mode(mode: LaserMode | Mode | str) -> None

turn_on() -> None

turn_off() -> None

`pychilaslasers.laser`

`pychilaslasers.Laser(com_port: str, calibration_file: str | Path | None = None)`

`comm: Communication` `property`

`system_state: bool` `property` `writable`

`mode: LaserMode` `property` `writable`

`tune: TuneMode` `property`

`sweep: SweepMode` `property`

`manual: ManualMode` `property`

`model: str` `property`

`calibrated: bool` `property`

`calibration: Calibration | None` `property` `writable`

`system: System` `property`

`trigger_pulse() -> None`

`calibrate(calibration_file: str | Path | None = None, calibration_object: Calibration | None = None) -> None`

`set_mode(mode: LaserMode | Mode | str) -> None`

`turn_on() -> None`

`turn_off() -> None`