TEC brought over eight systems to the USA over 1 meter in size. Seven 1-meter systems were installed on Mt. Wilson - a multi-array interferometer project for the search of planets near the closest stars. A few more large Cassegrain systems from 1m to 1.4m were made for Japanese subcontractors and the largest, a 1.4m Cassegrain system, ended up in an observatory in South Africa.

    In the late 90's, TEC decided to start their own production of optics and telescopes, and at that time they brought a complete line of equipment for testing glass and optical manufacturing to the USA. In 1998 they started production of optics in Golden, Colorado. TEC produced a line of Maksutov telescopes ranging from 6" to 10" diameter and continue to work on special optics for professional observatories. In the beginning of the new century they began working on a new product - Apochromatic refractors, and the first APO was made in the year 2000 ( APO200FL) and in 2002 started regular production of smaller refractors. The first production model of refractors was the APO140 F7 ED oiled triplet - which was a good choice for introduction to the market; later on TEC added larger models: APO160, APO180 and APO200. Apochromatic refractors make up the majority of their ongoing present and near future production.