Optima has recently announced the availability of a new product called the 3D-XL adapter. The 3D-XL will allow legacy 720p DLP video projectors to play 3-D images for 1080p sources, such as a 3-D BluRay player. Apparently this will only work if the legacy 720p projector comes with HDMI 1.3 inputs.

Model 3D-XL ($399 suggested retail) is billed as the first converter box that lets 720p 3D DLP projectors play 1080p 3D Blu-ray discs. As with all single projector 3D systems, active 3D glasses are required to view images in 3D.

via : Optoma Unveils 3D Adapter For 720p Projectors @ Twice.com