A display 1201 includes an array of light modulators 1208 that define a display plane, a light guide 1204 and front- and rear-facing reflective surfaces. The light guide 1204 includes a plurality of geometric light redirectors 1206, and at least 50% of the light guide's rear surface is parallel to the display plane. The rear-facing reflective surface is parallel to the display plane and includes a plurality of apertures.

Display apparatus with optical cavities

The invention relates to methods and apparatus for forming images on a display utilizing a control matrix to control the movement of MEMs-based light modulators.

Display methods and apparatus

Circuits for controlling display apparatus

Display devices incorporating shutter-based light modulators are disclosed along with methods of manufacturing such devices. The methods are compatible with thin-film manufacturing processes known in the art and result in displays having lower power-consumption.

Display apparatus and methods for manufacture thereof

Improved portable hand held devices having bright, high resolution MEMS display panels with shutters and optionally optical cavities having both front and rear reflective surfaces. Light-transmissive regions are formed in the front reflective surface for spatially modulating light.

Devices having MEMS displays

The sensing of the rotor position for synchronizing the drive of a multiphase brushless motor when driven in a "multipolar" mode is carried out by interrupting the driving current in at least one of the windings of the motor coupled with a zero-cross sensing circuit of the BEMF signal (BEMF DETECT CIRCUIT), by means of a first logic signal (ENABLE), enabling a logic gate (AND) for asserting a zero-cross event detected by the circuit, by a second logic signal (MASK) and simultaneously resetting the first (ENABLE) and second (MASK) signals after a certain period of time from the instant of interruption.

Detection of instantaneous position of the rotor of a brushless DC motor driven in a tripolar mode

The present invention relates a Pulse Width Modulation (PWM)/linear driver for an electromagnetic load by a bridge circuit of the type having a signal input and a signal output and at least two conduction control inputs for driving a voice coil motor in a linear mode and in a pulse width modulation. The bridge circuit is driven by a PWM converter coupled to one of said two control inputs and by a linear amplifier coupled to the other of said two control inputs.

PWM/linear driver for an electromagnetic load

A method is for driving a multiphase brushless motor with N windings connected in a star or in a polygonal configuration. The windings are driven according to a certain periodic voltage profile. The method includes cyclically keeping for a certain time interval at least one of the N windings in a fixed state of low or high saturation and applying to the other phase windings instantaneous voltages according to a predefined different periodic voltage profile such that the resultant voltages on the windings are coherent with the certain periodic voltage profile. The number of intervals, in an entire electrical period, in which the fixed high or low saturation state of one winding is produced, depends on the predefined driving profile and upon the number N of windings of the motor.

A method of PWM driving a brushless motor with digitally stored voltage profiles with reduced losses

The driving voltage of the motor is incremented a quantity proportional to the speed of the motor according to a proportionality factor that is adjusted to compensate the back electromotive force A method includes open-loop voltage control of a DC motor having a certain design speed constant, through a driving signal that is determined for imparting a certain acceleration to the motor and by generating a driving voltage of an output power stage to which the winding of the motor is connected as a function of the driving signal

Open-loop voltage driving of a DC motor

The present invention relates to a method and a circuit using the method thereof for minimising the phase errors during the driving of an electric motor, and a circuit using the method thereof, having a stator winding, a permanent magnet rotor assembly, and devices able to sense a rotor position, which comprises the following steps: a) generating of a rotor position signal ( 10, 14, 39 ), by means of said devices able to sense said rotor position; b) detecting at least two information from at least two edges ( 11, 12; 15, 16 ) of said rotor position signal ( 10, 14, 39 ) inside a measure period; c) generating a driving signal ( 9, 13, 38 ), in finction of said at least two information ( 11, 12; 15, 16 ) inside the measure period, so as to follow the rotor velocity.

Michele Boscolo

Papers

Detection of instantaneous position of the rotor of a brushless DC motor driven in a tripolar mode

PWM/linear driver for an electromagnetic load

A method of PWM driving a brushless motor with digitally stored voltage profiles with reduced losses

Open-loop voltage driving of a DC motor

Method for minimising the phase errors during the driving of an electric motor, and a circuit using the method thereof