# Secrets of the Bat Signal **URL:** \ **Category:** Cafe Society\ **Tags:** comic-books-manga\ **Created:** [March 7, 2022, 7:09pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623 "2022-03-07T19:09:23Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 7, 2022, 7:09pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623/1 "2022-03-07T19:09:23Z")
I keep sending “Light Touch” in to the offices of _Optica_ (the former Optical Society of America), and they have a backlog of them, and they release them on a schedule known only to them. but they published two of them just in time for Halloween on two different years – _I was a Teenage Optical Engineer_ and _Efficiently Killing Vampires with Ultraviolet Light_. (They have another Halloween one I sent them quite a while back, which i hope they’ll run this year or next.) The current issue has a piece that comes out just as the most recent Batman movie has been released. I’m not sure if they planned to print _Secrets of the Bat Signal_ now on purpose, or if it’s fortuitous. I’m not sure if everyone can open this, or if it only opens to members > **[022-024\_OPN\_03\_22.pdf](https://www.optica-opn.org/opn/media/Images/PDF/2022/0322/022-024_OPN_03_22.pdf?ext=.pdf)** > > 460.42 KB ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [March 7, 2022, 7:57pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623/2 "2022-03-07T19:57:43Z")
I could open it, and it’s another of your excellent columns. I’m doing a chapter on rays for my next book and I was started to see how many people had done sky projectors and how much newspaper attention they received. Of course, the images are so amazing that they beat food pills by a million miles. Charles Margolis especially. You can see a page from Modern Mechanix on [Quora](https://www.quora.com/Is-it-going-to-work-in-real-life-if-you-flash-a-real-batsignal-into-the-sky). The image used is an ad for toothpaste. Imagine those everywhere every night. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 7, 2022, 9:01pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623/3 "2022-03-07T21:01:27Z")
They used to project ads on the sides of buildings (just as the Bat Signal is projected on a building in Frank Miller’s _The Dark Knight Returns_) when they started this kind of thing. Eventually the cities passed ordinances against them because they were causing bottlenecks in pedestrian traffic. (I was a lot easier to project a legible ad on a building than on a cloud) ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [March 7, 2022, 11:05pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623/4 "2022-03-07T23:05:21Z")
What about the annoying, possibly illegal spam projected from a storefront onto the sidewalk? Often circular. e.g., [![](https://i.pinimg.com/originals/04/c6/dd/04c6ddedac521822dd0d780651c58208.jpg) ](https://i.pinimg.com/originals/04/c6/dd/04c6ddedac521822dd0d780651c58208.jpg) What are the optics? ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [March 7, 2022, 11:15pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623/5 "2022-03-07T23:15:19Z")
I wonder if Seattle has any regulations about non-physical signage. It would make for an interesting test case. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [March 8, 2022, 1:57pm UTC](https://boards.straightdope.com/t/secrets-of-the-bat-signal/960623/6 "2022-03-08T13:57:58Z")
> [@DPRK](#): > > What are the optics? Pretty straightforward imaging using a single, well-corrected lens. It’s basically the same thing that I wrote about above, only aimed downward at the sidewalk, rather than sideways at a building. Many thanks for the kind words, **Exapno.**