Process Date: January 2003

A large spot size, a rotary stage, and 10 W of laser power were used to seal this glass (borosilicate) pipette, producing a smooth, sealed end. In order to reduce localized stress on the pipette, a rotary stage turning at 350 RPM and a large 0.04" spot size (created by intentionally defocusing a five inch focal length lens a full 0.25" from the point of focus) was set up to heat the glass slowly. While the 0.075" diameter borosilicate pipette was rotating, it was heated for approximately four seconds by a Synrad J48-2 CO2 laser firing at 20% duty cycle, which delivered 10 W of CO2 laser energy into the glass. 

 
This 0.075"- diameter borosilicate glass pipette was sealed using 10W of CO2 laser power.