Phaser Type II

The Phased Energy Rectification Weapon Type II is a directed energy weapon and the standard issue sidearm of Starfleet armed forces. Like most Starfleet Phasers, it fires a steady beam of rapid nadions whose effect depends on chosen setting and target.
The Type II has sixteen intensity settings, the lowest of which causes momentary dizziness on normal humanoids. Set slightly higher it will stun for a duration dependant on the target's physiology, increasing intensity further will heat objects, then burn them, and the highest settings will totally vaporize a target.
Beam width can be modified too, but a wide dispersal comes at an enormous cost in intensity.
All hand-held Starfleet Phasers are gyro-stabilized, a sensor bar on top scans the wielders eye distance, angle and direction of focus and then compares it to the image of the target area captured by the emitter boresight. This way the Phaser's circuitry triangulates the chosen target, and the gyro motors align the beam emitter so it will be hit at center of mass. Gyro stabilization can be overridden, and the weapon will do so itself if it is unable to calculate a point of focus.
Because most of the aiming is done by the weapon itself as long as it is held in the general direction of the target, Starfleet weapons training usually requires shooting at tiny, fast moving dots that change colors on the range. This trains reflexes and quick focussing on a target.
When humanity set out to the stars, it was obvious that not everyone the explorators met could be expected to be friendly. Early weapons still had the classic pistol shape, a design used by almost every humanoid species in the galaxy. It was comfortable to use, but also instantly recognized as a weapon.
For later Phasers, Starfleet engineers came up with a shape that was more reminiscent of a remote control. It not only made away teams less likely to be immediately disarmed, many aliens were also much more cooperative when they didn't consider Starfleet officers to carry weapons with them.
Unfortunately the shape required unnatural twisting of the wrist to properly aim, and while the gyro motors usually compensate, they were angled down most of the time because of this.
It was decided that the Type II would have to be redesigned, and so it received a more angled grip that is more comfortable to hold as shown here. Miniaturization also made the weapon wholly more slender, at no loss in capability. The new Sarium Krellide power pack even has a higher capacity than the old one, and reloading in the field is much easier.