A standard left-click can easily map to turning a laser pointer off, then back on. Most laser pointers have a button you press to turn them on and release to turn them off, so when using a standard laser pointer, a left-click would consist of releasing the button then pressing it again to flash the laser off then back on. Unfortunately, click-and-drag fails horribly with this mapping, because the laser is off during what is mapped to the button-down portion of the click-and-drag event.

A more complex 'click' model was needed. At first glance one might think simply decreasing the intensity of the laser pointer during the drag portion of a click-and-drag would work. Unfortunately this runs into two serious complications: (1) no 'standard' laser pointers implement an intensity-control button that brightens or dims the pointer, and (2) making the pointer dim makes it much harder to track.

After a lot of thought, two different approaches were found that worked. The first would be the easiest to implement, but would require manufacturing custom laser pointers. The second would be more difficult to implement, but would permit control with any standard off-the-shelf laser pointer!

Method 1

Build a laser pointer with more than one spot! With more than one spot, the single spot can be left on all the time, and additional spots or patterns can be lit up when other buttons are pressed on the pointer device. Laser pointer modules were obtained and a 3-spot pointer was quickly built up that had an on-off switch that controlled the whole pointer. When it was on, the main emitter was always on. Two other buttons controlled the other two emitters. Pressing the left button turned on one of the emitters, while pressing the right button turned on both additional emitters forming a 'triangle' with the three spots. Software was written to track the number of active emitters, and from that the software could determine whether any buttons were pressed. The main emitter was used as the 'hot spot" for the overall pointer, so any click or drag operations used the main emitter as the action location.

While writing the software, Mr. Hansen discovered that additional control mechanisms were opened up by having multiple spots. One could track the rotational orientation of the cluster of spots! When thinking about what might be a useful action to trigger using rotation, Mr. Hansen found that popping up a keyboard to enable data entry was an incredibly useful ability. By clicking the left-button in a data entry field, then rotating the pointer while the button was held down, an action was generated which popped up a virtual keyboard, permitting the operator to click on keys to enter text into the field.

The new pointer worked great! Mr. Hansen created several demo videos, two of which he has made available for viewing on this website.

But how does one get the same level of control while using a single-spot off-the-shelf laser pointer? Click on the link below for more!

SIMPLE...DIRECT...BRILLIANT!