Lasers for multiphoton microscopy

Coherent just sold its 1000th Chameleon system. That’s roughly how many of the similarly-priced Lamborghini Countach LP500s were sold. That was in the 1980s. Coherent has been selling Chameleons since 2003, I think.

Together with Newport Spectra-Physics’ MaiTai, these one-box Ti:Sapphire lasers greatly reduced the technical overhead of a multiphoton microscope. No more hand tuning and re-aligning after every change in wavelength.

Nature Photonics recently ran a piece on the history of the Ti:Sapphire laser. Today, the power levels have increased, the variations have grown (e.g., bolt-on prechirpers), the tuning ranges have broadened, the prices have come down a little bit, but the duopoly is still in place.

Are there any alternatives to these two companies?
In some cases, yes. Here are some possibilities to consider:

Fiber lasers/Ytterbium lasers

Amplitude Systemes (not a typo, French) sells ultrafast oscillators around 1030-1064nm (good for some RFPs) and cost about a tenth of what a Ti:Sapphire system costs. As for looks, it’s a question of taste, but they’re certainly not boring. Fianium has similar offerings. Bonus: lower repetition rate (around 10 MHz) may allow for brighter fluorescence by decreasing triplet state occupancy (for example).

DIY lasers

Dejan Vucinic’s famous 2007 paper described how he built his own Ytterbium-doped KY(WO4)2 (Yb:KYW) laser tuned to about 981 nm with a 113 MHz pulse rate and a 310 fs pulse width. This paper is really a tour de force in homebrew multiphoton imaging. It’s a pity that the project is “now mostly abandoned for lack of funding and general interest in its further development”. I wish I had deeper pockets, Dejan.

Kit lasers

Sciner sells Ti:Sapphire kits with specifications that don’t look too bad really, other than low power (which is largely a function of the pump laser). I’m interested to see the stability, though. Especially when changing wavelengths. There’s no service contract, but then who cares; just replace it anytime something on it breaks.

Del Mar Photonics

This is a smaller company with some interesting products: Trestles Finesse Ti:Sapphire (pdf 1, pdf 2), Teahupoo one-box (pdf), a Cr:Forsterite laser at 1230-1270nm (pdf), and fiber lasers.

Used

I should note, especially given a recent post, that both Spectra-Physics (Newport) and Coherent will sell used/reconditioned lasers. The discounts aren’t deep, but they are enough to warrant consideration.

Footnote

Here’s an excerpt from the Nature Photonics article mentioned above:

Ti:Sapphire (Ti:Sa) was initially proposed and demonstrated as a near-infrared gain medium in 1982, and was commercialized by Spectra-Physics in 1988 with the launch of a continuous-wave laser. This was followed in 1990 by a picosecond mode-locked oscillator, and in 1991 with a femtosecond version.

Denk, Stickler and Webb’s paper came out in 1990. They were using the picosecond model that had just been released that year.