I've found this vendor of photo radar jammers that work in the way I described.
http://1-radar-laser-jammers-detectors.com/our-store/photo-radar/index.php These will only work if the photo radar equipment uses flash, which apparently is usually, but not always, the case.
http://www.sense.bc.ca/equipmnt.htm This sort of thing costs about $350.
There are also commercial laser gun jammers, which do in fact appear to work. "Blinder" is one brand. The bad news is that the latest models of police laser guns report to the officer that he is being jammed, and even the make of the jamming device. Supposedly at least one new model is able to defeat the jamming, though I am not sure how this is done. These jammers are also about $350+. They are not prohibited by Federal law (unlike radar gun jammers), but some states (including CA) prohibit them.
http://www.radarbusters.com/support/speedlabs/radar-laser-jamming.asp I'm having a hard time thinking of an effective and attractive place on the 911, near the headlights, to mount the two detector/jammer units.
Hmm, so equipping my car with photo radar jamming, laser gun jamming, plus a Valentine 1 would cost nearly $1000.