Long Term Output Power Stability (±1% Over 900 Hours)
>600 mW Output Power and <8 fs Pulse Width
Turnkey, Maintenance-Free Operation
Low Cost of Ownership
Thorlabs' Octavius® Femtosecond Laser is a maintenance-free, ti:sapphire oscillator that emits one of the broadest spectra commercially available. It has a high average output power of >600 mW, while maintaining a <8 fs transform-limited pulse width. The broadband spectrum of this ultrafast laser system is well suited for amplifier seeding, particularly for Optical Parametric Chirped Pulse Amplifiers (OPCPA), or use in pump/probe experiments. For detailed specifications, please see the Specs tab.
The Octavius ti:sapphire fs laser is ideal for life science applications such as multiphoton or coherent anti-Stokes Raman scattering (CARS) imaging. With a pulse duration of less than 8 fs, this laser provides an exceptionally high peak power of more than 700 kW and a large spectral bandwidth spanning more than 200 nm at -10 dB. This wide bandwidth, covering more than half the typical tuning range of most ti:sapphire oscillators, allows for the simultaneous excitation of several spectrally separated fluorophores at their optimal absorption wavelengths without tuning.
Technology The Octavius fs laser is a soft-aperture Kerr-lens mode-locked (KLM) ti:sapphire laser. The laser cavity incorporates dispersion-compensating mirror (DCM) pairs, which are required for smooth, high-precision group delay control over the octave-wide bandwidth. The fabrication of these unique mirror pairs requires the optimization of a 150-coating-layer design.
Mechanical Design Ease of use and mechanical robustness were at the forefront of the design for the Octavius fs laser. Unlike typical laser designs, which use traditional translation stages for tuning and alignment, the alignment of the Octavius is controlled via a unique flexure stage design that eliminates the various materials generally used for springs, bearings, and frames while still maintaining unprecedented accuracy and repeatability. Custom tooling and fixtures guarantee stress-free machining during production and therefore minimize drifts and misalignment of the laser cavity caused by stress relaxation.
Pump Laser The Octavius Ti:Sapphire Oscillator includes an integrated pump laser. The pump laser is based on state-of-the-art Optically Pumped Semiconductor Laser (OPSL) technology, which allows for high compactness. As an option, the Octavius is available without a pump laser; in this case, an input port can be used to direct the external pump laser into the ti:sapphire oscillator.
Please contact email@example.com for more information about this system, customization options, or to request a quote.
The output pulse is chirped to account for dispersive materials outside the laser. To obtain the transform-limited pulse width, dispersion compensation is needed to counter-chirp and compress the pulse.
Safe practices and proper usage of safety equipment should be taken into consideration when operating lasers. The eye is susceptible to injury, even from very low levels of laser light. Thorlabs offers a range of laser safety accessories that can be used to reduce the risk of accidents or injuries. Laser emission in the visible and near infrared spectral ranges has the greatest potential for retinal injury, as the cornea and lens are transparent to those wavelengths, and the lens can focus the laser energy onto the retina.
Safe Practices and Light Safety Accessories
Thorlabs recommends the use of safety eyewear whenever working with laser beams with non-negligible powers (i.e., > Class 1) since metallic tools such as screwdrivers can accidentally redirect a beam.
Laser goggles designed for specific wavelengths should be clearly available near laser setups to protect the wearer from unintentional laser reflections.
Goggles are marked with the wavelength range over which protection is afforded and the minimum optical density within that range.
Post appropriate warning signs or labels near laser setups or rooms.
Use a laser sign with a lightbox if operating Class 3R or 4 lasers (i.e., lasers requiring the use of a safety interlock).
Do not use Laser Viewing Cards in place of a proper Beam Trap.
Lasers are categorized into different classes according to their ability to cause eye and other damage. The International Electrotechnical Commission (IEC) is a global organization that prepares and publishes international standards for all electrical, electronic, and related technologies. The IEC document 60825-1 outlines the safety of laser products. A description of each class of laser is given below:
This class of laser is safe under all conditions of normal use, including use with optical instruments for intrabeam viewing. Lasers in this class do not emit radiation at levels that may cause injury during normal operation, and therefore the maximum permissible exposure (MPE) cannot be exceeded. Class 1 lasers can also include enclosed, high-power lasers where exposure to the radiation is not possible without opening or shutting down the laser.
Class 1M lasers are safe except when used in conjunction with optical components such as telescopes and microscopes. Lasers belonging to this class emit large-diameter or divergent beams, and the MPE cannot normally be exceeded unless focusing or imaging optics are used to narrow the beam. However, if the beam is refocused, the hazard may be increased and the class may be changed accordingly.
Class 2 lasers, which are limited to 1 mW of visible continuous-wave radiation, are safe because the blink reflex will limit the exposure in the eye to 0.25 seconds. This category only applies to visible radiation (400 - 700 nm).
Because of the blink reflex, this class of laser is classified as safe as long as the beam is not viewed through optical instruments. This laser class also applies to larger-diameter or diverging laser beams.
Lasers in this class are considered safe as long as they are handled with restricted beam viewing. The MPE can be exceeded with this class of laser, however, this presents a low risk level to injury. Visible, continuous-wave lasers are limited to 5 mW of output power in this class.
Class 3B lasers are hazardous to the eye if exposed directly. However, diffuse reflections are not harmful. Safe handling of devices in this class includes wearing protective eyewear where direct viewing of the laser beam may occur. In addition, laser safety signs lightboxes should be used with lasers that require a safety interlock so that the laser cannot be used without the safety light turning on. Class-3B lasers must be equipped with a key switch and a safety interlock.
This class of laser may cause damage to the skin, and also to the eye, even from the viewing of diffuse reflections. These hazards may also apply to indirect or non-specular reflections of the beam, even from apparently matte surfaces. Great care must be taken when handling these lasers. They also represent a fire risk, because they may ignite combustible material. Class 4 lasers must be equipped with a key switch and a safety interlock.
All class 2 lasers (and higher) must display, in addition to the corresponding sign above, this triangular warning sign
Pulsed Laser Emission: Power and Energy Calculations
Determining whether emission from a pulsed laser is compatible with a device or application can require referencing parameters that are not supplied by the laser's manufacturer. When this is the case, the necessary parameters can typically be calculated from the available information. Calculating peak pulse power, average power, pulse energy, and related parameters can be necessary to achieve desired outcomes including:
Protecting biological samples from harm.
Measuring the pulsed laser emission without damaging photodetectors and other sensors.
Exciting fluorescence and non-linear effects in materials.
Pulsed laser radiation parameters are illustrated in Figure 1 and described in the table. For quick reference, a list of equations are provided below. The document available for download provides this information, as well as an introduction to pulsed laser emission, an overview of relationships among the different parameters, and guidance for applying the calculations.
Period and repetition rate are reciprocal:
Pulse energy calculated from average power:
Average power calculated from pulse energy:
Peak pulse power estimated from pulse energy:
Peak power and average power calculated from each other:
Peak power calculated from average power and duty cycle*:
*Duty cycle () is the fraction of time during which there is laser pulse emission.
Figure 1: Parameters used to describe pulsed laser emission are indicated in the plot (above) and described in the table (below). Pulse energy (E) is the shaded area under the pulse curve. Pulse energy is, equivalently, the area of the diagonally hashed region.
A measure of one pulse's total emission, which is the only light emitted by the laser over the entire period. The pulse energy equals the shaded area, which is equivalent to the area covered by diagonal hash marks.
The amount of time between the start of one pulse and the start of the next.
The height on the optical power axis, if the energy emitted by the pulse were uniformly spread over the entire period.
The optical power at a single, specific point in time.
The maximum instantaneous optical power output by the laser.
A measure of the time between the beginning and end of the pulse, typically based on the full width half maximum (FWHM) of the pulse shape. Also called pulse duration.
The frequency with which pulses are emitted. Equal to the reciprocal of the period.
Is it safe to use a detector with a specified maximum peak optical input power of 75 mW to measure the following pulsed laser emission?
Average Power: 1 mW
Repetition Rate: 85 MHz
Pulse Width: 10 fs
The energy per pulse:
seems low, but the peak pulse power is:
It is not safe to use the detector to measure this pulsed laser emission, since the peak power of the pulses is >5 orders of magnitude higher than the detector's maximum peak optical input power.