Alvan Clark & Sons

Alvan Clark & Sons was a historic American manufacturer of precision optical equipment and astronomical telescopes. The business grew from the work of optical craftsman Alvan Clark and later became a family enterprise involving his sons. During the late nineteenth and early twentieth centuries, refracting telescopes remained important tools for astronomical observation, and the company supplied telescope objectives and complete instruments to observatories. It became particularly associated with large-aperture achromatic refractors and played a significant role in the history of American telescope making. The company eventually ceased operating as a continuing telescope brand as reflecting telescopes and the optical manufacturing industry developed. Some of its instruments and optical components remain of historical and collecting interest.

Alvan Clark & Sons originated in the optical manufacturing work of American craftsman Alvan Clark. Clark initially worked as a portrait painter before turning to optical grinding and beginning to produce astronomical telescope objectives in the mid-nineteenth century. The year 1846 is commonly associated with the establishment of his optical business. As his sons joined the production and management of the enterprise, it operated under the name Alvan Clark & Sons. During the second half of the nineteenth century, the company became one of the major American makers of refracting telescopes, with expertise in glass grinding, achromatic objective design, and the assembly of large precision instruments.

• 1846

• Astronomical refracting telescopes

  The company’s best-known product line, built around large refracting designs and precision optical systems for observatories, research institutions, and professional astronomical observation.

• Achromatic telescope objectives

  Precision objectives for refracting telescopes, designed to reduce chromatic aberration and representing a major part of the company’s contribution to astronomical optics.