Laser Technology  

 History

Laserix was specialised in the development and manufacture of lasers for veterinary, medical and industrial use. 

ML01 ruby laser welding machines.

The first generation of industrial lasers machines was developed by Prof. P. Ravussin in 1966 for the welding of the watch spirals. It was a world first. This first generation machines was using a ruby 150mm length and of 6,35mm diameter (YAG crystal was not yet invented). In these early ML01 machines, an analogical calculator compensates the relatively fast ageing of the “optical pumping” flash lamp.

  

Watch spirals welding: A BissectronÒ device splits the laser beam in two such a way that the two spots are weld in the same time.

 Today the spiral is welded to the axis

 

At this time, a “good” ruby laser was able to pierce a rwo Swiss franc silver coin. It corresponds to an energy output of about 10 joules. The first ML01 machine was used to weld the watch spiral on its coupling ring. Later on, ML01 machines where sold to Omega Watch Company to weld a watch part simultaneously in 3 points.

 

One of these watches was worn by Astronaut Edwin Aldrin in the moon module.

 

 

 

 

Arming wheel of the Omega Speedmaster welded simultaneously in three points (inside the black circles)

 

The ultimate development of the ruby lasers ML01 machines was the construction of huge double machines delivered to a Siemens factory. They served to weld the spring and the contacts of miniature relays.  Each has a “MultisectronÒ”: this patented device divides the laser beam before the optic and therefore welds several points at a time.  

Prof. P. Ravussin was successful where the hughe Siemens laser laboratory has failed.

The double ML01 laser machines under construction

 

ML05D Hard stones laser drilling machines

A new synthetic laser crystal Nd:YAG was invented in 1964. It is today the most widely used active laser medium in solid-state lasers. Laser made with Nd:YAG have much better performance then the ruby lasers. However the maximum energy for a given crystal size is much less.

Ruby stone is widely use in high quality mechanical watches and jewel bearing instruments. Mechanical drilling has been replaced in the 70th with laser drilling. Laser drilling of sapphire or ruby is a very complex phenomenon that is not easy to master. Our ML05 laser drilling machines have been optimised over decades of industrial production. 

 

 

 

 

 

 

Ruby stones in a mechanical watch

 

As soon as the Nd:YAG crystal becomes available in the early seventeen, Prof. P. Ravussin started to develop watch stones drilling machines. It is a difficult task because the laser energy shall be very stable, the laser beam shall be perfectly round, and the machine shall be mechanically perfectly stable over millions of shots.

 
 

 

 

 

Watch stone undrilled and finished

 

 

 

 

 

 

 

 

Hard stones drilling is made with specially designed laser machines. The laserix  ML01 to ML06 machines have mass produced billions of stones of various diameter and thickness.

Basically the process is as following:  A laser beam is focused to the raw watch stone. At the focal point the temperature becomes so high that the ruby material is evaporated and expulsed.

 

Technology

The jewel bearing drilling (sapphire, ruby, etc.) is mainly a percussion drilling. A succession of laser shots is needed to pierce the stone. The number of shots and the total energy of each shot shall be programmed according to the thickness of the stone and the diameter of the hole to be pierced. Each shot is composed of hundreds of laser spikes of very high peak power and very short duration separated by dead time. It is this succession of spikes that helps to drill holes much longer that the diameter.

The ejected material is volatilized.

The spectrum of the drilling flame shows that the temperature of the plasma reaches 5500K. The emission line of Cr3+ in the ruby stone at 694,3nm can be easily recognized in the following spectrum as well as other Cr3+  lines.

Actually the peak power needed to drill can only be reached with flash lamp laser pumping.

 

The ML05 laser drilling machines are able to pierce holes of a diameter ranging from a few micron to 2/10 of mm ore more on sapphire and ruby. The change from one type of stone to another one is made rapidly. For larger diameter hole trepanning machining shall be used: a serial of small holes are pierced over the circumference. Narrow holes can be pierced to a length of a few millimetres.

Floor Space

The ML05 watch stones drilling machine keeps the vertical configuration of the earlier machines that minimized the required floor space to approx. 700mm x 600mm only. The height of the machine is 2600mm.


Watch stones drilling workshop

Laser type

Nd:YAG flash pumped

Wavelength

1064nm

Repetition rate

Max 3Hz

Beam diameter

4mm or 5mm

Beam quality

Diffraction limited

cooling

Demineralized water

Pulse to pulse energy stability

<0.1%rms

Output energy stability over 8 hours

<0.5%rms

Temperature

15C – 30C

 










 

Controls

The ML05 hard stone laser drilling machine is controlled by means of a computer installed in the base of the machine. The hard disk is a solid state drive (no moving part) that has 100+ Year Life Expectancy (MTBF). The motherboard is an “Ultra Durable 2” designed model with top quality long life components.

The control software is the bug free, goof protected Ml05 software.  The operator can configure the machine for different type of stones (number of shots, energy of each shot). Each configuration can be saved and retrieved when the same kind of drilling shall be realised.

Instructions

It exists 2 courses: a general academic course on lasers taught at Ecole Nationale Vétérinaire d'Alfort near paris (France) and a specific course on the adjustment and use of laer ML05 machines.

 Availability

Most electronic parts of the ML05 drilling machine are available from stock.

Please call induplan@vtxnet.ch for more informations

ALM05 high frequency switching current generator