Mechanical mice The German company
Telefunken published on their early ball mouse on 2 October 1968. created a ball mouse in 1972 while working for
Xerox PARC. The ball mouse replaced the external wheels with a single ball that could rotate in any direction. It came as part of the hardware package of the
Xerox Alto computer. Perpendicular
chopper wheels housed inside the mouse's body chopped beams of light on the way to light sensors, thus detecting in their turn the motion of the ball. This variant of the mouse resembled an inverted
trackball and became the predominant form used with
personal computers throughout the 1980s and 1990s. The Xerox PARC group also settled on the modern technique of using both hands to type on a full-size keyboard and grabbing the mouse when required. The ball mouse has two freely rotating rollers. These are located 90 degrees apart. One roller detects the forward-backward motion of the mouse and the other the left-right motion. Opposite the two rollers is a third one (white, in the photo, at 45 degrees) that is spring-loaded to push the ball against the other two rollers. Each roller is on the same shaft as an
encoder wheel that has slotted edges; the slots interrupt infrared light beams to generate electrical pulses that represent wheel movement. Each wheel's disc has a pair of light beams, located so that a given beam becomes interrupted or again starts to pass light freely when the other beam of the pair is about halfway between changes. Simple logic circuits interpret the relative timing to indicate which direction the wheel is rotating. This
incremental rotary encoder scheme is sometimes called quadrature encoding of the wheel rotation, as the two optical sensors produce signals that are in approximately
quadrature phase. The mouse sends these signals to the computer system via the mouse cable, directly as logic signals in very old mice such as the Xerox mice, and via a data-formatting IC in modern mice. The driver software in the system converts the signals into motion of the mouse cursor along X and Y axes on the computer screen. The ball is mostly steel, with a precision spherical rubber surface. The weight of the ball, given an appropriate working surface under the mouse, provides a reliable grip so the mouse's movement is transmitted accurately. Ball mice and wheel mice were manufactured for Xerox by Jack Hawley, doing business as The Mouse House in Berkeley, California, starting in 1975. Based on another invention by Jack Hawley, proprietor of the Mouse House,
Honeywell produced another type of mechanical mouse. Instead of a ball, it had two wheels rotating at off axes.
Key Tronic later produced a similar product. Modern computer mice took form at the
École Polytechnique Fédérale de Lausanne (EPFL) under the inspiration of Professor
Jean-Daniel Nicoud and at the hands of
engineer and
watchmaker André Guignard. This new design incorporated a single hard rubber mouseball and three buttons, and remained a common design until the mainstream adoption of the scroll-wheel mouse during the 1990s. In 1985,
René Sommer added a
microprocessor to Nicoud's and Guignard's design. Through this innovation, Sommer is credited with inventing a significant component of the mouse, which made it more "intelligent"; Another type of mechanical mouse, the "analog mouse" (now generally regarded as obsolete), uses
potentiometers rather than encoder wheels, and is typically designed to be
plug compatible with an analog joystick. The "Color Mouse", originally marketed by
RadioShack for their
Color Computer (but also usable on
MS-DOS machines equipped with analog joystick ports, provided the software accepted joystick input) was the best-known example.
Optical and laser mice Early optical mice relied entirely on one or more
light-emitting diodes (LEDs) and an imaging array of
photodiodes to detect movement relative to the underlying surface, eschewing the internal moving parts a mechanical mouse uses in addition to its optics. A laser mouse is an optical mouse that uses coherent (laser) light. The earliest optical mice detected movement on pre-printed mousepad surfaces, whereas the modern LED optical mouse works on most opaque diffuse surfaces; it is usually unable to detect movement on specular surfaces like polished stone. Laser diodes provide good resolution and precision, improving performance on opaque specular surfaces. Later, more surface-independent optical mice use an optoelectronic sensor (essentially, a tiny low-resolution video camera) to take successive images of the surface on which the mouse operates. Battery powered, wireless optical mice flash the LED intermittently to save power, and only glow steadily when movement is detected.
Inertial and gyroscopic mice Often called "air mice" since they do not require a surface to operate, inertial mice use a tuning fork or other
accelerometer (US Patent 4787051) to detect rotary movement for every axis supported. The most common models (manufactured by Logitech and Gyration) work using 2 degrees of rotational freedom and are insensitive to spatial translation. The user requires only small wrist rotations to move the cursor, reducing user fatigue or "
gorilla arm". Usually cordless, they often have a switch to deactivate the movement circuitry between use, allowing the user freedom of movement without affecting the cursor position. A patent for an inertial mouse claims that such mice consume less power than optically based mice, and offer increased sensitivity, reduced weight and increased
ease-of-use. In combination with a wireless keyboard an inertial mouse can offer alternative ergonomic arrangements which do not require a flat work surface, potentially alleviating some types of repetitive motion injuries related to workstation posture.
3D mice A 3D mouse is a computer input device for
viewport interaction with at least three degrees of freedom (
DoF), e.g. in
3D computer graphics software for manipulating virtual objects, navigating in the viewport, defining camera paths, posing, and desktop
motion capture. 3D mice can also be used as
spatial controllers for
video game interaction, e.g.
SpaceOrb 360. To perform such different tasks the used
transfer function and the device stiffness are essential for efficient interaction.
Transfer function The virtual motion is connected to the 3D mouse control handle via a
transfer function. Position control means that the virtual
position and
orientation is proportional to the mouse handle's deflection whereas velocity control means that
translation and
rotation velocity of the controlled object is proportional to the handle deflection. A further essential property of a transfer function is its interaction metaphor: • Object-in-hand metaphor: An exterocentrical metaphor whereby the scene moves in correspondence with the input device. If the handle of the input device is twisted clockwise the scene rotates clockwise. If the handle is moved left the scene shifts left, and so on. • Camera-in-hand metaphor: An egocentrical metaphor whereby the user's view is controlled by direct movement of a virtual camera. If the handle is twisted clockwise the scene rotates counter-clockwise. If the handle is moved left the scene shifts right, and so on. Ware and Osborne performed an experiment investigating these metaphors whereby it was shown that there is no single best metaphor. For manipulation tasks, the object-in-hand metaphor was superior, whereas for navigation tasks the camera-in-hand metaphor was superior.
Device stiffness Zhai used and the following three categories for device stiffness: •
Isotonic Input: An input device with zero stiffness, that is, there is no self-centering effect. •
Elastic Input: A device with some stiffness, that is, the forces on the handle are proportional to the deflections. •
Isometric Input: An elastic input device with infinite stiffness, that is, the device handle does not allow any deflection but records force and torque.
Isotonic 3D mice Logitech 3D Mouse (1990) was the first ultrasonic mouse and is an example of an isotonic 3D mouse having six degrees of freedom (6DoF). Isotonic devices have also been developed with less than 6DoF, e.g. the Inspector at Technical University of Denmark (5DoF input). Other examples of isotonic 3D mice are
motion controllers, i.e. is a type of
game controller that typically uses accelerometers to track motion. Motion tracking systems are also used for
motion capture e.g. in the film industry, although that these tracking systems are not 3D mice in a strict sense, because motion capture only means recording 3D motion and not 3D interaction.
Isometric 3D mice Early 3D mice for velocity control were almost ideally isometric, e.g.
SpaceBall 1003, 2003, 3003, and a device developed at
Deutsches Zentrum für Luft und Raumfahrt (DLR), cf. US patent US4589810A.
Elastic 3D mice At DLR an elastic 6DoF sensor was developed that was used in Logitech's SpaceMouse and in the products of
3DConnexion. SpaceBall 4000 FLX has a maximum deflection of approximately at a maximum force of approximately 10N, that is, a stiffness of approximately . SpaceMouse has a maximum deflection of at a maximum force of , that is, a stiffness of approximately . Taking this development further, the softly elastic Sundinlabs SpaceCat was developed. SpaceCat has a maximum translational deflection of approximately and maximum rotational deflection of approximately 30° at a maximum force less than 2N, that is, a stiffness of approximately . With SpaceCat Sundin and Fjeld reviewed five comparative experiments performed with different device stiffness and transfer functions and performed a further study comparing 6DoF softly elastic position control with 6DoF stiffly elastic velocity control in a positioning task. They concluded that for positioning tasks position control is to be preferred over velocity control. They could further conjecture the following two types of preferred 3D mouse usage: • Positioning, manipulation, and docking using isotonic or softly elastic position control and an object-in-hand metaphor. • Navigation using softly or stiffly elastic rate control and a camera-in-hand metaphor.
3DConnexion's 3D mice have been commercially successful over decades. They are used in combination with the conventional mouse for
CAD. The Space Mouse is used to orient the target object or change the viewpoint with the non-dominant hand, whereas the dominant hand operates the computer mouse for conventional CAD
GUI operation. This is a kind of space-multiplexed input where the 6 DoF input device acts as a graspable user interface that is always connected to the view port.
Force feedback With
force feedback the device stiffness can dynamically be adapted to the task just performed by the user, e.g. performing positioning tasks with less stiffness than navigation tasks. File:Logitech spacemouse 3D-IMG 8429-black.jpg|Logitech spacemouse 3D. On display at the
Bolo Computer Museum,
EPFL, Lausanne File:Silicon Graphics Ball-IMG 4192.jpg|Silicon Graphics SpaceBall model 1003 (1988), allowing manipulation of objects with
six degrees of freedom File:Logitech 3D ultrasonice mouse 1990-IMG 7952-gradient.jpg|Logitech 3D Mouse (1990), the first ultrasonic mouse File:Space-Navigator.jpg|A modern six-degrees-of-freedom (6 DOF) 3D mouse (2007) File:Spaceball 4000 FLX - Optical Assembly.JPG|Mechanism of the modern 6 DOF mouse consisting of infrared LEDs and detectors with occluders that move with the ball
Tactile mice In 2000,
Logitech introduced a "tactile mouse" known as the "iFeel Mouse" developed by
Immersion Corporation that contained a small
actuator to enable the mouse to generate simulated physical sensations. Such a mouse can augment user-interfaces with
haptic feedback, such as giving feedback when crossing a
window boundary. To surf the internet by touch-enabled mouse was first developed in 1996 and first implemented commercially by the Wingman Force Feedback Mouse. It requires the user to be able to feel depth or hardness; this ability was realized with the first electrorheological tactile mice but never marketed.
Pucks Tablet digitizers are sometimes used with accessories called pucks, devices which rely on absolute positioning, but can be configured for sufficiently mouse-like relative tracking that they are sometimes marketed as mice.
Ergonomic mice As the name suggests, this type of mouse is intended to provide optimum comfort and avoid injuries such as
carpal tunnel syndrome,
arthritis, and other
repetitive strain injuries. It is designed to fit natural hand position and movements, to reduce discomfort. When holding a typical mouse, the
ulna and
radius bones on the
arm are crossed. Some designs attempt to place the palm more vertically, so the bones take more natural parallel position. Increasing mouse height and angling the mouse topcase can improve wrist posture without negatively affecting performance. Some limit wrist movement, encouraging arm movement instead, that may be less precise but more optimal from the health point of view. A mouse may be angled from the thumb downward to the opposite side – this is known to reduce wrist pronation. However such optimizations make the mouse right or left hand specific, making more problematic to change the tired hand.
Time has criticized manufacturers for offering few or no left-handed ergonomic mice: "Oftentimes I felt like I was dealing with someone who'd never actually met a left-handed person before." Another solution is a pointing bar device. The so-called
roller bar mouse is positioned snugly in front of the keyboard, thus allowing bi-manual accessibility.
Gaming mice These mice are specifically designed for use in
computer games. They typically employ a wider array of controls and buttons and have designs that differ radically from traditional mice. They may also have decorative monochrome or programmable RGB LED lighting. The additional buttons can often be used for changing the sensitivity of the mouse or they can be assigned (programmed) to
macros (i.e., for opening a program or for use instead of a key combination). It is also common for game mice, especially those designed for use in
real-time strategy games such as
StarCraft, or in
multiplayer online battle arena games such as
League of Legends to have a relatively high sensitivity, measured in
dots per inch (DPI), which can be as high as 25,600. DPI and CPI are the same values that refer to the mouse's sensitivity. DPI is a misnomer used in the gaming world, and many manufacturers use it to refer to CPI, counts per inch. Some advanced mice from gaming manufacturers also allow users to adjust the weight of the mouse by adding or subtracting weights to allow for easier control. Ergonomic quality is also an important factor in gaming mouse, as extended gameplay times may render further use of the mouse to be uncomfortable. Some mice have been designed to have adjustable features such as removable and/or elongated palm rests, horizontally adjustable thumb rests and pinky rests. Some mice may include several different rests with their products to ensure comfort for a wider range of target consumers. Gaming mice are held by
gamers in three styles of
grip: • Palm Grip: the hand rests on the mouse, with extended fingers. • Claw Grip: palm rests on the mouse, bent fingers. == Connectivity and communication protocols ==