The Lighting Science Group said Tuesday it has acquired light-emitting-diode company Lamina Lighting for $4.5 million in cash.

Dallas -based Lighting Science Group plans to use part of a $20 million loan from the Bank of Montreal to pay for the acquisition, the company said. Lighting Science makes LED lighting systems, controllers, dimmers and other LED components.

Lamina, based in Westampton, N.J., makes LED lighting systems and components. It was spun off from Sarnoff Corp., which makes video surveillance technologies and other imaging and security products, in 2001.

Aside from the $4.5 million, Lighting Science has agreed to pay Lamina an additional amount of up to $10.5 million in the second quarter of 2010, depending on Lamina’s 2009 sales.

But even if the total deal reaches $15 million, the sale price is hardly impressive considering that Laminahad raised $37.5 million in venture capital by 2005 and an additional $7 million in 2007. Investors include Morgenthaler Partners, Redshift Ventures and Granite Global Ventures.

The purchase is the latest in the LED lighting market. Cree, which makes LED components, bought LED Lighting Fixtures for about $77 million in cash and stock in February (see Cree to Buy Firm Founded by Its Former Execs).

In the past, LEDs were relegated mostly to indicator lights on consumer electronic gadgets, traffic lights and headlamps for camping, but the market for light fixtures made from LEDs – which manufacturers claim shine more brightly, use energy more efficiently and last longer than conventional light bulbs – has been growing.

Improvements in LED designs and materials have made the lights more affordable. A New York Times story on Sunday noted the trend among factory and commercial building managers, who are choosing LEDs for long-term savings.

But LED lights are still too expensive to replace compact fluorescent or incandescent light bulbs in every home. Philips Lighting, part of consumer electronics giant Royal Philips Electronics in the Netherlands, plans to introduce its first series of LED lights for homes in Europe in September. The lights, under the brand Ledino, would cost €69 ($107.56) per bulb.

Many lighting companies believe LEDs could one day replace conventional bulbs used in homes and offices. As a result, major light bulb makers have been launching new products to target a broader market. Investors are placing their bets on LED startups that aim to solve key problems, such as overheating.

Billerica, Mass.-based Luminus Devices said in March it had raised $72 million in venture capital (see Luminus Closes $72M to Light Up New Applications). Another startup, Nuventix in Austin, Texas, earlier this month raised $14 million to market its devices to cool LEDs (see Wakonda, Nuventix Raises Millions).

One startup, D.Light Design in India is creating affordable LEDs to compete with kerosene lanterns in developing countries (see D.Light Shines Light Where Energy Doesn’t Flow).

The promise of better LED lights for the masses has sparked a lot of university research in the field. Purdue University researchers have been developing LEDs using less expensive and more heat-conductive silicon, MIT Technology Review reported Tuesday.