BALTIMORE -- Fans watching NFL games on television have grown accustomed to the imaginary yellow line that runs across the field in accord with the first-down marker.

That first-down line could become part of the in-game experience at all 32 NFL stadiums.

Alan Amron, with financial backing from former NFL player and broadcaster Pat Summerall, has developed the First Down Laser System. Amron says the system projects a first-down line across the field that can be seen in the stadium and on TV.

Amron, an entrepreneur and concept promoter, first met with the NFL in 2003 and again in 2009. There may be future meetings soon.

NFL spokesman Greg Aiello says, "We have not been convinced that it would work for us, but we are open to further discussion after the season."