Audax Group has acquired Luminator Technology Group LLC from private equity firm Levine Leichtman Capital Partners.

Plano, Texas-based Luminator designs and manufactures illuminated display, lighting and passenger communications systems for the bus, rail and aerospace markets. Terms of the deal were not disclosed.

Audax plans to grow the company organically and through add-on acquisitions. The Boston private equity firm focuses on investing in lower middle-market companies and has more than $5 billion in assets under management. Audax portfolio company United Recovery Systems recently purchased Array Services Group

Levine Leichtman, headquartered in Los Angeles, has about $7 billion in capital under management. In November, the firm bought Genova Diagnostics Inc., a clinical laboratory.

Kirkland & Ellis was Audax's legal counsel. Robert W. Baird & Co. advised Luminator on the deal. GE Capital Corp. BNP Paribas Securities and American Capital Ltd. provided financing.