nice stylus

In order to increase the distance that a touch screen stylus can be sensed at (distance from touch screen) from approximately 1/2 a centi…

In relation to what? There are augmented capacitive styli that use a battery to increase the ‘flow’ of electrons from the screen to the tip, however capacitive reactance is what it is, the inherent resistance.

So to mitigate this…for extra accuracy you would want another datapoint for reference.

Bluetooth is usually the next level.

Ok after your edit I see. You want to know how a stylus can be re-engineered so it can be seen without making physical contact with the digitizer.

Well that’s an interesting question. The way a capacitive screen works…the physicality of it, is a sensor being able to tell the difference between the dielectrics in a touch screen environment: Air, and the molecular space between your finger it a stylus when it makes contact.

Capacitors have 2 conductive plates separated by an insulator. For the touch sensor to detect the difference in the resistive change between contact and no contact, electrons need flow between the display and your stylus. In this case the capacitor plates are  your finger or the stylus, and the other is the sensor in the display. The insulator is air. Once you close enough range to remove the air, you get current to flow, the resistance across the insulator drops, and the 4 sensors in each corner get a portion of that current depending on how far away your finger is from each sensor. This provides the display/touch controller with position.

For your scenario to work, you need to generate an arc from the stylus to the display.

Capacitive sensing measures the delta between the dielectric change in air, and when you touch the display. When you touch it, there is a small current between your body and the digitizer. The 4 sensors in the corners each have input to the display controller and some math between the 4 figures out position.

Since an arc wouldn’t provide any resistance from the point where the arc ‘ends’ to where it touches the display, it’s unlikely that the sensors in the corner would be able to figure out position, as the value they would each get from the flow of the arc would be equal.

So, the display controller would be able to tell that the arc touches the center of the screen no matter where on the display the arc makes contact. Giving you an effective ‘finger in the middle tap and hold’ gesture.

But this would never be possible, because an arc of electricity contains so much current and voltage that your circuit would no longer function.

Here is what a pulsed arc does to an LCD.

Here is a guy using a taser vs. iPhone.

Imagine what a sustained arc would do.

In order to increase the distance that a touch screen stylus can be sensed at (distance from touch screen) from approximately 1/2 a centi…

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