(written from a Production point of view)
Joseph Westheimer (18 May 1916 – 6 November 1998; age 82) was a special effects artist on Star Trek: The Original Series. He was the co-recipient in 1967 of an Emmy Award for Individual Achievements in Cinematography for his work along with Darrell Anderson and Linwood G. Dunn.
Westheimer began working in the movie industry at the age of 15, first as a messenger at the Warner Bros. studio, and later in the prop department. After graduating in electrical engineering from the California Institute of Technology, he joined the special effects department of the studio, then led by Byron Haskin (who later worked as associate producer on "The Cage"). During World War II, Westheimer worked on propaganda and army training films. Afterwards, he returned to the field of special effects and started his own firm, The Westheimer Company in 1955.
The Westheimer Company provided special effects for several series, including The Twilight Zone and The Big Valley, and later worked on major films, such as Star Wars V - The Empire Strikes Back.
Along with other special effects houses, The Westheimer Company was hired by Robert Justman and Edward K. Milkis after they realized that the Howard Anderson Company alone is not able to fulfill the demands of a series such as Star Trek. (Inside Star Trek: The Real Story)