Having started his career in 1945 as a teacher at a vocational school in the Czech glass-making center Novy Bor, Mr. Libensky was inseparable, artistically and personally, from Ms. Brychtova. They went on to influence generations of glass makers in Europe, Japan and the United States.

His massive colored glass castings are scattered around Prague, where they are an integral part of many public works, from the facade of the National Theater to the windows of St. Vitus Cathedral. In the United States, his works are in the collections of several museums, including the Metropolitan Museum of Art and the Corning Museum of Glass in Corning, N.Y.

A retrospective of the Libenskys' work is at the 20th century Art Collection of the National Gallery in Prague and will be the first exhibition at the new Museum of Glass in Tacoma, Wash. The show will open there on July 4.

''He was the most important glass artist of our time,'' said Thomas Buechner, the founding director of the Corning Museum. ''He elevated glass to the level of major architectural sculpture.''

''Alchemy'' was how Mr. Libensky impishly described the process of creating the huge forms of solid color for which he and his wife were known. The truth lay deeper, in Mr. Libensky's rigorous classical training and in the deep and close artistic cooperation with his wife, which lasted nearly half a century.

The two met at the Zelezny Brod glass-making school, which had been founded by Ms. Brychtova's father. The town, about 60 miles from Prague, has been a glass-making center for centuries.

''When I came to Zelezny Brod, I made a drawing of a head that was shaped like a bowl,'' Mr. Libensky recalled in an interview. ''Ms. Brychtova came and said, 'Mr. Libensky, may I turn this drawing into something three-dimensional?' I said 'Yes, try it,' and she tried so successfully that we continued to work together. It worked because I trained as a painter and she trained as a sculptor.''

The couple first came to world attention at the Czech pavilion of the 1958 World's Fair in Brussels, with their flagstone-size colored glass panels with reverse reliefs of animals. The crackdown that followed the 1948 Communist putsch in Czechoslovakia had ravaged the country's art world, but had curiously left the door open for glass artists, who were seen as politically acceptable artisans. Orders soon came for glass pieces to adorn factories and hotels.

''Art went in through the back door,'' Ms. Brychtova recalled.

But politics was never far behind. Inspired by the Prague Spring reform movement of the late 1960's, the Libenskys began ''The River of Life,'' a huge glass artwork that was a tribute to Czechoslovakia's struggle for freedom in the 20th Century.

It was shown at the 1970 World's Fair in Osaka, Japan, but by then hard-line Communists were beginning a belated crackdown on artists after the Soviet Union's 1968 invasion of Czechoslovakia, and censors ordered the Libenskys to sandblast Soviet Army bootprints from the work. When they returned home from Osaka, the Libenskys' reputation was assured, but they were expelled from the Communist Party and forbidden to travel abroad together.

The international exposure brought the couple to the attention of the young American glass artist Dale Chihuly, who was then studying in Venice. On a whim, Mr. Chihuly traveled to Zelezny Brod and called on the Libenskys unannounced. Mr. Chihuly, perhaps America's most prominent glass artist, invited them to the Pilchuk [sic] glass school in Washington State.

''What he brought, what was really important, was that his interest was in art,'' not in glass simply as a craft, Mr. Chihuly said of Mr. Libensky's approach.

At home, Mr. Libensky was highly regarded as a teacher. ''He insisted that we learn classical techniques, how to paint and sculpt with the light of nature,'' said Marian Karel, a prominent Czech glass artist. ''It was two years before we ever touched glass.''

Short and rotund with an elfish grin and a warm, bubbling personality, Mr. Libensky was also a bit of a showman, given to greeting students and lecture audiences with outstretched arms and a cry of ''fantasticky.''

He was thrown out of the academy by the Communists in 1987, and never returned to full-time teaching. Instead, he traveled widely and sold many works abroad.

Near the end of his life, Mr. Libensky, formerly a pack-a-day smoker, was told he had lung cancer. His work shifted from the vibrant greens, blues and reds he had been using to heavy grays and deep browns. His last major work, a series of eight-foot-tall, vestmentlike sculptures in a thick, translucent gray, were inspired, Ms. Brychtova said, by the X-rays of his own body that Mr. Libensky saw so many times during his battle with cancer."