Plesty Taiko PDL M1 Device

A PLESTY device module for the PicoQuant Taiko PDL M1: a laser driver that powers a pulsed/continuous-wave (cw) diode laser head. The module sets the pulse repetition rate and the power, switches between pulsed and cw operation, and reads the lock state, the calibrated average power and the temperatures.

The module is built so the laser never stays on by accident: see Safety.

Supported hardware

The Taiko PDL M1 driver with a laser head connected, over USB. It talks to the driver through PicoQuant's own library, PDLM_Lib.dll, so it runs on Windows. Everything else, including the simulator (mock), works without the library or the hardware.

Installation

git clone https://gitlab.com/plesty/hub/devices/picoquant/plesty-taiko-pdl-m1.git
cd plesty-taiko-pdl-m1
uv sync

PicoQuant's software and PDLM_Lib.dll

PDLM_Lib.dll is PicoQuant's. Its license forbids passing it on, so it is not in this repository and never will be. Install PicoQuant's Taiko software yourself (from PicoQuant); it puts the library on the PC.

The module runs in 64-bit Python and needs the 64-bit library. It looks for it at

C:\ProgramData\Taiko PDL M1\API\x64\PDLM_Lib.dll

If yours is elsewhere, set TAIKO_DLL_PATH (in .env or the environment) to the file or its folder. Many lab scripts use the 32-bit copy (...\API\Win32\) with 32-bit Python; the module refuses that file and says so, because a 64-bit program cannot load it.

Quick start

Copy .env.example to .env, then connect the driver by USB, switch it on, and close PicoQuant's own Taiko program (only one program can hold the driver).

from plesty.taiko_pdl_m1 import Device

# address: empty = the first Taiko found, "0".."7" = a USB index, a serial number,
# or "mock" = the simulator
with Device(address="mock") as laser:
    laser.write("laser_mode", "pulsed")
    laser.write("repetition_rate", 10_000_000)  # Hz
    laser.emission_on()  # releases the lock, power stays 0
    laser.write("power_permille", 100)  # 10 % of the maximum at this rate
    print(laser.query("power"))  # calibrated average power, mW
    laser.emission_off()  # power 0, then lock

As a server for experiments: uv run python -m plesty.taiko_pdl_m1 (port from TAIKO_TCP_PORT, default 5555).

Safety

• Power 0 before every lock. With the laser locked the driver reads 0 and refuses power changes, but it keeps the setting and brings it back when the lock is released. So the module sets the power to 0 first, and after each unlock reads the power back and sets a restored value to 0.
• Locked on disconnect. disconnect (also when the server stops) sets power 0 and engages the software lock before it closes the driver.
• A driver found emitting is secured. Connecting to a driver that is unlocked with power above 0 (for example after a killed server) sets power 0 and the lock, with a warning.
• Key and interlock cannot be overridden. The software lock is separate from the key switch and the interlock connector; the module can release only its own lock. locked shows the overall state, emission_on reports why it is still locked.
• power_permille is refused while locked and on an external trigger; a laser_mode switch is refused while locked (call emission_on first); writing soft_lock goes through emission_on / emission_off.

Reference

Power is given in permille (thousandths) of the maximum, which depends on the repetition rate; average power in linear power mode grows with the rate at a fixed permille.

Communication

USB through PDLM_Lib.dll, driver index 0 to 7 (up to eight drivers). Environment, see .env.example: TAIKO_ADDRESS, TAIKO_DLL_PATH, TAIKO_TCP_PORT.

Field test

tests/field_test.py (generic gates, never turns the laser on) and tests/bench_questions.py (unlocks the laser briefly at up to 5 % power; run it with the beam blocked or on a power meter) are run by hand on the PC with the driver; see docs/index.md.