INTRODUCTION
Laser cutting is a fast and effective method for creating prototypes out of acrylic, wood, fabric, and many other materials. Laser cutters can be thought of as plotters that cut instead of drawing; they can "print" any 2D file within minutes. They can connect directly to any standard PC or Mac. Though laser cutters can cut only flat materials, cut parts can be layered or assembled with slots to generate functional, structural 3D models. Lasers cut sharp and accurate edges that require no sanding or cleaning. The power and ease of use of laser cutters has resulted in their regular use in the Stanford Product Design program.

MOTIVATION
The Tangible Media Group explores physical interfaces to digital information. As such, it has a regular need to fabricate physical prototypes. (The Triangles Physical/Digital construction set, as well as parts of the Luminous Room, were manufactured by outsourcing to laser cutters.) But any group that relies on attractive, functional prototypes could take advantage of its availability. For example, groups can make professional looking signs and displays from colored acrylic.

NOTE: While professional laser shops are competent, the time lags incurred in outsourcing greatly compromises the convenience of laser cutting. Owning a laser cutter will encourage much more productive and innovative use.

AVAILABLE SYSTEMS
Laser cutting systems vary widely in size and performance. After some research, two models were examined in detail. While very different in price, both are capable of cutting laminated plastic, acrylic, wood, vinyl, paper, and fabric up to 1/4" thick. They can also engrave laminated plastic, acrylic, coated metal, wood, glass, stone, leather, and rubber. Below are listed the key specifications of each: LaserCamm Model 4000 Menlo Park, CA (system used at Stanford) $100k w/o exhaust system 35x21" cutting area about 54x30" bed area 550 lbs. 35W laser delivery time 12 weeks according to brochure (may be less) Universal Laser ULS-25PS Scottsdale, AZ (local rep in Bedford MA) $30k incl. exhaust system 24x18" cutting area 40x20" bed area 205 lbs. 25W laser delivery time unknown The Universal system has a much smaller cutting area, but it is smaller, lighter, and far less expensive. Delivery and service should probably be more rapid as well, as the vendor has a local representative. This is the system is recommended for purchase. Of course, large objects (screens, tables, etc.) can still be outsourced to professional shops.

INSTALLATION
The recommended system measures 38Hx43Wx34D and has wheels. Though it is no larger than a mid-sized table, it has an exhaust system which must be vented to the outdoors. This should not be costly, but choosing a site must be done carefully. Also, the system should be connected to a dedicated PC with CAD and drawing software.

CONCLUSION
Laser cutters transform digital information into physical prototypes safely, rapidly, and accurately. A system should be obtained for the Media Lab as soon as possible.