Femtosecond laser processing is an essential tool in modern science and industry. But what exactly are femtosecond lasers and why are they important?
First, it should be realized that these measurements of time are incredibly short: a femtosecond is equal to one quadrillionth of a second (in other words, one millionth of a billionth of a second!) See Figure 1.
| Millisecond | 10–3 = 1/1,000 | One thousandth of a second |
| Microsecond | 10–6 = 1/1,000,000 | One millionth of a second |
| Nanosecond | 10–9 = 1/1,000,000,000 | One billionth of a second |
| Picosecond | 10–12 = 1/1,000,000,000,000 | One trillionth of a second |
| Femtosecond | 10–15 = 1/1,000,000,000,000,000 | One quadrillionth of a second |
Figure 1. Milliseconds to Femtoseconds Chart
One quadrillionth of a second is such an infinitesimally short amount of time, it’s difficult to imagine. If you think about the how long a second is and expand it out, this is what we need to comprehend:
| 1 x 60 | 60 seconds | One minute |
| 1,000 | One thousand seconds | 16 minutes and 40 seconds |
| 1,000,000 | One million seconds | 11 days, 13 hours, 46 minutes, and 40 seconds |
| 1,000,000,000 | One billion seconds | 31.69 years |
| 1012 | One trillion seconds | 31,688.74 years |
| 1015 | One quadrillion seconds | 31,688,738,506 years (over 31.6 billion years) * |
Figure 2. One second to one quadrillion seconds chart
* This is much longer than the current estimated age of the universe, which is about 13.8 billion years
To put this into perspective, a hummingbird’s wing flaps approximately 70 times per second (Figure 3). This converts to around 14.29 trillion femtoseconds for one flap of a hummingbird wing.
Hummingbird wing flaps:
~ 70 times per second
One flap = ~1/70th of a second
One flap = ~14.29 trillion femtoseconds
Figure 3. Hummingbird wings flap approximately 70 times per second.
Media credit to Paul MacDonald
Another way to look at femtoseconds is in relation to distance:
-
- Light travels from the Earth to the moon in about 1.255 seconds.
Figure 4. Speed of light from Earth to the moon.
Animation by Dr. James O’Donoghue using NASA imagery
-
- In one femtosecond, light only travels about 1/333 the thickness of a sheet of paper (or one three hundredth the width of a human hair).
What are femtosecond lasers?
With rapid technological advancements, laser technology has evolved significantly over the years, leading to breakthroughs in various industries.
Instead of emitting light continuously, femtosecond lasers emit concentrated light pulses that are so short, they only last for a few femtoseconds. Despite being so brief, these pulses are incredibly powerful and accurate. The frequency at which femtosecond lasers can emit pulses of light range from several MHz to much higher for advanced systems.
Because the laser pulses are so fast, they can cut or shape materials very precisely without heating them up or causing damage to the surrounding area. Traditional lasers might overheat the material, but femtosecond lasers avoid this problem because their pulses are so quick that the material doesn’t have time to absorb much heat.
What are real-world applications?
Femtosecond and picosecond lasers are used in many fields, including medical devices (catheter drug delivery systems and other flow metering devices), manufacturing (for creating tiny, detailed parts), and even art (for intricate engravings). Femtosecond laser processing is like using a tiny, ultra-fast light scalpel that can make precise cuts or shapes in materials without causing any unwanted side effects such as thermal shock, micro-cracking, or localized melting.
Where is the future of laser technology heading?
Looking ahead, we will see lasers that have pulses even shorter than a nanosecond, entering what’s called a “photoablation” process. In simpler terms, as the pulses get shorter, the laser becomes incredibly powerful, potentially reaching levels of power in the millions of watts. This intense power can break apart molecules and remove material by turning it into plasma (a hot, electrically charged gas).
Bold Laser Automation Extends Femtosecond Laser Technology
Bold Laser Automation, Inc., an innovator in laser technology solutions, offers laser systems for an array of industrial applications, including femtosecond and picosecond laser processing. These lasers have revolutionized areas such as micromachining, surface processing, and material characterization.
Our innovative approach lowers the costs of industrial picosecond and femtosecond optical beam delivery systems, and so making these sophisticated systems available to a broader marketplace. Our modular tooling designs offer enhanced flexibility and adjustability, empowering industries like medical devices and microelectronics to have greater access to these systems.
For more information on how we make these systems affordable, see our recent news story, “A New Method to Lower Costs of Industrial Picosecond and Femtosecond Optical Beam Delivery Systems.”
See our latest femtosecond laser system shipping this month in our press release, “Femtosecond Laser Processing System Sets New Benchmarks in Micromachining, Cutting and Scribing.”
Recent Comments