TopMode CHARM Control0 pages

TopMode
405

TopMode
445

TopMode
488

TopMode
515

TopMode
633

TopMode
685

Laser specications
Operation
Wavelength

443 nm

488 nm

514 nm

No

0

Contrast

< 5 MHz (< 0.01 pm)

Coherence length

> 25 m

CHARM

Active coherence stabilization, included

ASE suppression

40 dB typ.

100

200

300

400

100

200

300

400

100

200

300

400

100

200

300

400

100
50
0

405.16
405.14

< 1 pm/h (< 0.5 pm/h typ.), peak-peak

Linewidth

940

0

Upon request, accuracy 0.5 nm

Wavelength stability *

960

0

685 nm

± 2 nm

Wavelength selection

633 nm

λ (nm)

Wavelength tolerance

Wavelength tuning

23
22
21

0

cw, single (fixed) frequency
405 nm

Ambient conditions

1.0
0.5
0.0

35 dB typ.

Output power, free-space

50 mW
(100 mW **)

30 mW

30 mW
(60 mW **)

25 mW

30 mW

25 mW
(50 mW **)

15 mW

15 mW
(30 mW **)

15 mW

15 mW

Time (h)

25 mW

Output power, ber-coupled

Pressure (mbar)

Model

TopMode – Performance with CHARM

Relative Temperature
power (%)
(°C)

Specications

15 mW

Power stability *

Typ. < 0.5% (STD/mean) / h

Intensity noise (RMS)

380-hr long-term test of TopMode 405 with CHARM stabilization.

≤ 0.1% @ 10 Hz .. 10 MHz
Linear, > 100 : 1, 90° (free-space version)

Beam shape

Collimated, circular, ∅ 1 mm, ellipticity < 10% ***

Spatial mode

TEM00, M2 < 1.5 (< 1.2 typ.)

Key features

Optical isolation

Built-in, > 30 dB

Fiber coupling

Optional

General and environmental specications
TopMode CHARM Control,
for operation of one or two TopMode lasers

Electronics
Warm-up time

< 10 min from standby

Environmental temperature (operating)

Range 15 – 30 °C, stability ± 3 °C

Environmental temperature (transport)

0 – 40 °C

Humidity
Operating voltage
Power consumption

80

Power (mW)

Polarization

100

· Diode laser with best wavelength &
coherence stability

60

· Wavelengths:
405 / 445 / 488 / 515 / 633 / 685 nm

40

· Up to 100 mW single-frequency power
· Linewidth < 5 MHz, coherence length > 25 m

20
0

· Integrated “CHARM” control for
mode-hop-free operation
405 nm 445 nm 488 nm 515 nm 633 nm 685 nm

High Power at a Single Frequency

Maintain Your CHARM

The TopMode lasers employ state-of-the-art diode technology to achieve the highest single-frequency output
power of any direct diode-based system. The 405 nm
model offers as much as 100 mW – an industry record! At
the well-established HeNe wavelength of 633 nm, the corresponding TopMode device provides an output of 30 mW.

Varying ambient conditions – temperature, air pressure
and humidity levels – affect the performance of externalcavity diode lasers, resulting in mode-hops and occasional
incoherent, “multi-mode” emission intervals. TOPTICA’s
unique CHARM technology provides an active stabilization
of the laser’s coherence. The design ensures continuous
single-frequency operation – and thus excellent longterm stability of the lasing wavelength and output power,
as well as an extremely low intensity noise.

The TopMode lasers feature a spectral width of less than
5 MHz, translating into a coherence length greater than
25 m. All models exhibit an excellent stability of wavelength
and output power. Users can choose between a free-beam
output and optional ber-coupling, realized with TOPTICA’s
patented SmartDock™ coupler.

In laser-based inspection and metrology tasks, CHARM
ensures accurate measurements by preventing sudden
step changes of the laser’s power or frequency.

Free-space output power of the TopMode laser family.

Non condensing
100 – 120 V / 220 – 240 V AC, 50 – 60 Hz (auto detect)

TopMode – Better than a Blue HeNe

CHARM: Active Coherence Control

Sophisticated measurement tasks in interferometry, holography, scatterometry and Raman spectroscopy require top
performance lasers. The spectral properties must remain extremely stable – a single mode-hop can spoil an ongoing
measurement.

“CHARM” (CoHerence-Advanced Regulation Method) denotes an active stabilization scheme for the temporal coherence of the TopMode lasers. Inside the laser head, a beam splitter taps off a fraction of the laser beam, and a detector unit monitors the coherence properties of the emitted radiation. A closed feedback loop then acts on the laser
current to maintain stable coherence properties; in other words: narrow-linewidth, single-frequency laser operation.

Typ. < 70 W, max. 150 W (incl. CHARM Control)

Digital communication interface
Laser head dimensions
Laser head weight
Controller dimensions
Controller weight

Ethernet, USB
Free-beam: 192 x 80 x 60 mm
Fiber-coupled: 218 x 80 x 60 mm
1.5 kg
480 x 290 x 50 mm (L x W x H)
4 kg

* With CHARM activated ** Optional high-power version *** 488 nm laser has an elliptical beam prole
Please note: Specications are subject to change without further notice.

TOPTICA’s new TopMode lasers operate as easily as a HeNe, but also offer higher power and blue wavelengths.
The TopMode series sets records in terms of power, coherence and wavelength stability. The proprietary CoHerenceAdvanced Regulation Method (CHARM) provides an active stabilization of the lasers’ coherence and ensures continuous
single-frequency operation. TopMode and CHARM means nothing less than reliable 24/7 operation.
Replacing bulky, power-consuming gas ion lasers has never been this simple!

In the case of strongly varying environmental conditions, users can choose to run a proactive CHARM correction
sequence (e.g., 1-2 times per day), allowing the regulator to determine the best-suited set-point for the stabilization
scheme. The long-term measurement shown on this page demonstrates the extreme stability of closed-loop operation
even without any intervening correction runs.