Ok, so the line is aimed at a sector. Inside this sector it hits various objects. It should recognise two objects of your interest. But the light also hits other objects in the background. If we'd get a scan of say a 90 degree sector, we'd get a distance for each degree. Or each 10th of degree. Depending on some accuracy. Say we have an array of 900 values, which are the distances to anything in the sector. From here we would pick two directions that could be the two objects we are interested in. This could work! But I still think a single laser beam would be a better approach. A mirror would aim the laser and make the 90 degree sweep. Make it fast enough so it would feel like a one shot.