3D Crystal Evolution

3D Crystal, 3D Laser Crystal, and 3D Crystal Images, terms commonly used to describe many of the crystal awards and promotional products on this site, are short hand for what should be more precisely called marking solid objects by creating patterns of controlled localized laser induced sub-surface damage.

On our Patent Info page, the origins of the technology are described as part of the history for the '496 patent which covers this marking or engraving technique. During the decades since this technique was invented, the technology has undergone a considerable evolution. What began as a crude and difficult to control method, has developed into a sophisticated method for controlling thousands of very short (femtosecond) high intensity Nd:YAG laser pulses within glass, crystal, and plastics. The 3D Laser imaging techniques used to create the high definition Crystal Awards products we offer are the result of two generations of improvements in the technology.

Early efforts and experiments in controlled sub-surface laser engraving suffered from a number of problems, including difficulty controlling scattering of the subsurface damage.  This was particularly problematic along the axial vector of the laser beam, which limited any ability to create a consistent and identifiable mark within the medium.   When Prof. Clement invented a methodology for controlling the damage depth and scattering, a milestone was achieved. 

By controlling axial scattering of the laser damage, Prof. Clement's breakthrough extended the capabilities of this technology to include representations of full and accurate spatial characteristics of an object or mark.

3D Imagery: More Than Just  X, Y, and Z 

The term 3D obviously refers to the three dimensions of space (width, depth, and length), however, when used in the context of media, its meaning is much more complex.

                 

   

Since the Renaissance, artists have understood that by including various visual cues in a 2 dimensional representation of a scene, the third dimension is inferred by the human viewer.  Techniques such as utilizing a vanishing point and foreshortening were developed during the Renaissance.  See:  

http://en.wikipedia.org/wiki/Vanishing_point

                       

http://en.wikipedia.org/wiki/Perspective_(graphical)#Foreshortening

Such 2-D visual cue based representations of 3D scenes, however, ignore an adaptation of vision shared by virtually all species of animals that have eyes: stereoscopy.  Stereo vision provides two laterally spaced views of a scene or object to the viewer simultaneously.  By providing these laterally spaced views, a limited but actual axial (depth) representation of a scene or object can be perceived.  In the 19th century, a means for stereoscopic 3D representations of scenes was invented by Sir Charles Wheatstone, a renowned British scientist and engineer whose legacy rivals Edison.  

http://en.wikipedia.org/wiki/Stereoscopic_image

Wheatstone's invention is currently experiencing a global resurgence in popularity, although the methodology he invented nearly a century and a half ago is virtually identical to the one used in the 3D film Avatar. By presenting fixed 2D images to each eye of the viewer, the brain perceives actual depth.  A variation on stereoscopy known as "wiggle stereoscopy" creates a 3D image effect by alternating the stereo views.  Although perhaps too distracting for practical applications, this simple illusion is illuminating:

                          

Stereoscopic illusions remain illusions, however, and anyone who has unconsciously moved their head to see "behind" objects presented in such scenes has encountered the limit of these methods.  A true 3D representation must allow the viewer to view the represented scene or object from any angle or distance while simultaneously modifying the presented pair of stereo images.   

A century after Wheatstone's invention, the Laser and the coherent light emitted by Lasers made the development of the next breakthrough possible, the hologram.

Our next installment will explore coherent light, the hologram, and the Nd-YAG Laser, the workhorse of subsurface engraving.  Stay tuned....