therefore led to heat-strengthened glass. The difference between the two is the cooling process in production, whereby tempered glass is cooled much faster and therefore there may be more uneven forces potent in the glass. Heat-strengthened glass goes through a longer cooling process and decreases such possibility. Tempered glass can even go through a Heat Soaked Test to significantly decrease possibilities of self-explosion, and these improvements have provides architects with much more freedom and less risks.

In Fei & Cheng's design of Nankang Software Park Phase II, we used the so-called "Double Low-E Glass"; possibly the first large-scale application in Taiwan of this glass type, which provides good light penetration and thermal insulation. It was a newly imported type of glass at the time, and its thermal coating is very effective when used in insulating glass. Insulating glass is very commonly used overseas, but not often in Taiwan. The main reason is the certain increase in building costs. However, we consider the high quality of this office building, built in an energy saving and environmental, conscious era. Hence, even though the initial investment was high, but the electricity fees saved every year can quickly recoup this investment. More importantly, it reflects little light to the exterior environment, increases the comfort of the interior environment, and possibly increases the work efficiency of the building users. These are all benefits that are hard to quantify but we should pay more attention to.

In recent years, great improvements to ceramic spandrel glass, ceramic silkscreen glass etc. has brought the color dimension to the world of glass.
In the past, colors of glass had to rely on reflective tints or coating and hence most of them came only in plain colors. There was already gold-color coating in the early days, but it affected the lighting color of the interiors. Today's reflective coatings and paints offer new endless possibilities. Reflective coatings have fine pores that cannot be seen by the human eye, allowing the same daylight effect on the interior no matter what color the exterior appears to be, and paint coating techniques have allowed glass to be even more brightly colored. In Fei & Cheng's design of Inotera Memories Inc. 

Headquarters, the colored ceramic spandrel glass that we used is a good example. The original concept was brought up by our collaborating German architect, and we were worried that this type of glass may affect interior lighting, and also if the fritted parts on glass may be printed with crispness and precision, which were proven to be unnecessary worries. This experience built up our confidence, and we made another application of the same kind at entrance canopies at Taipei Hsinyi Line subway stations. The shape of the canopies are of two curves with different radius, and the part facing pedestrian sidewalk is glazed with fritted glass. This application provides a sense of shelter on the roadway side while not obstructing natural lighting.
The application and expressiveness of glass can only get richer. Structural glass, curved glass, glass with double curvature, etc. provide us with structural strength, form, and color of glass for many different possibilities. In the near future, even the architects's imagination may no longer be the limiting factor. It is said that under the definition of Physics, glass is considered a super-cooled liquid form of ceramic material since it is never crystallized. Although this definition seems abstract, it nevertheless informs us that glass may be treated as a liquid material, shaped to form our architecture. Yet because the number of its possibilities are so high, it is hard to have complete control over, and demands even more knowledge and creativity. So let all of us in the architectural field, work together to push the horizon even further!