In digitizing tablets, the technology that radiates an electric field from the tablet surface and is detected by the cursor/stylus is known as the electrostatic method.

Introduction / Context:
Digitizing tablets convert physical pen or puck positions into digital x,y coordinates. Several sensing principles exist: electrostatic (electric field coupling), electromagnetic (inductive coupling), and sonic (time-of-flight of sound). Recognizing which principle corresponds to an electric field emitted by the tablet and picked up by the cursor is key to understanding device behavior and accuracy.

Given Data / Assumptions:

• The tablet actively radiates an electric field.
• The cursor/stylus detects that field via capacitive or electrostatic coupling.
• We must distinguish this from magnetic field or acoustic methods.

Concept / Approach:
Electrostatic (capacitive) systems establish an alternating electric field over the tablet surface. The cursor alters or senses this field, allowing the controller to compute position from coupling changes. Electromagnetic systems instead use coils and magnetic fields for inductive coupling; sonic systems use ultrasonic transducers to triangulate position from time-of-flight. Raster is a display scanning concept, not a digitizer sensing principle.

Step-by-Step Solution:
Match “electric field radiated from tablet” to “electrostatic” sensing.Exclude electromagnetic (magnetic field), sonic (acoustic waves), and raster (display scanning).Select “Electrostatic.”

Verification / Alternative check:
Vendor literature often describes electrostatic or capacitive coupling for tablets that can sense proximity without contact—a hallmark of electric-field approaches.

Why Other Options Are Wrong:
Electromagnetic: magnetic/inductive, not electric field radiation.Sonic: uses sound, not electric fields.Raster: pertains to image scanning on displays, not tablet sensing.None of the above: incorrect because “Electrostatic” is correct.

Common Pitfalls:
Confusing electrostatic with electromagnetic; assuming “raster” applies because of grid-like electrodes—it does not define the sensing principle.

Final Answer:
Electrostatic