A method of manufacturing an optical semiconductor device including: forming a mesa structure including a first conductivity type cladding layer, an active layer and a second conductivity type cladding layer in this order on a first conductivity type semiconductor substrate, an upper most surface of the mesa structure being constituted of an upper face of the second conductivity type cladding layer; growing a first burying layer burying both sides of the mesa structure at higher position than the active layer; forming an depressed face by etching both edges of the upper face of the second conductivity type cladding layer; and growing a second burying layer of the first conductivity type on the depressed face of the second conductivity type cladding layer and the first burying layer.

A manufacturing method for an excimer laser that includes a reflective Echelle diffraction grating includes obtaining information of a wavelength of a light source, a blazed order, a repetitive pitch of the grating, a material of the grating, and a predefined orientation ratio B/A that is a ratio between that a diffraction efficiency A of the blazed order and a diffraction efficiency Bb of an order lower by one order than the blazed order, and determining an initial value of a blaze angle based upon these pieces of information.

An intra-cavity frequency doubled OPS-laser includes a laser-resonator terminated by a plane mirror and a mirror-structure of an OPS-chip. The resonator is folded by three fold-mirrors. The fold-mirrors are supported on a vibration-isolation plate supported by isolation posts above a base-plate. The plane mirror and the mirror-structure of the OPS-chip are mounted back to back on opposite parallel surfaces of a mounting block. The mounting-block is supported on the base-plate and extends through an aperture in the vibration-isolation plate. Movement of the vibration-isolation plate with respect to the base-plate does not change the resonator length.

An EUV light generation system includes a driver laser comprising a master oscillator such as a semiconductor laser, a spatial filter, gas slab amplification devices, relay optical systems, and high-speed axial-flow amplifiers. The slab amplification devices include beam adjusting optical units disposed, respectively, at input and output sides of the slab amplifiers SA to convert the beam profile and/or polarization direction and/or an elongated direction of the beam profile with the slab amplifiers is parallel to a free space axis AF of the slab waveguides, i.e. parallel to the discharge electrodes.

A high power fiber laser system emitting a substantially diffraction limited beam with a Gaussian intensity profile includes a single mode (“SM”) neodymium fiber pump source outputting a SM pump light; a seed laser operative to emit a SM signal light at a wavelength greater than that of the pump light; a SM DWM receiving and multiplexing the SM pump and signal lights. The disclosed system further includes a booster fiber amplifier which is configured with a frustoconically-shaped ytterbium (“Yb”) doped core receiving the pump and signal lights and configured with a small diameter input end which supports only a SM and a large diameter output end which is capable of supporting the SM and high order modes (:HOM”). The booster further has a cladding surrounding and coextending with the core, the core being configured for having intensity profiles of respective SMs of pump and signal lights overlap one another so that an overlap integral substantially equals to one (1) along an entire length of the core. The SM of the light signal extracts substantially the entire energy from the pump mode leaving the HOMs without amplification necessary to affect a quality of the diffraction limited beam of the system in a MW peak power range and hundreds of watt average power range.

A method for quasi-synchronous tuning of wavelength or frequency of grating external-cavity semiconductor laser and a corresponding semiconductor laser are provided. A grating or mirror is rotated around a quasi-synchronous tuning point (Pq) as rotation center, so as to achieve the frequency selections by grating and resonance cavity in quasi-synchronous tuning, wherein the angle of the line between the quasi-synchronous tuning point (Pq) and a conventional synchronous tuning point (P0) with respect to the direction of light incident on the grating is determined according to the angle difference between the incidence angle and diffraction angle of light on the grating. According to present invention, approximately synchronous tuning of laser is achieved with a simple and flexible design.

An apparatus comprising an optical medium, a power splitter coupled to the optical medium, a first delay line coupled to the power splitter such that the power splitter is positioned between the first delay line and the optical medium, a first comb reflector coupled to the first delay line such that the first delay line is positioned between the first comb reflector and the power splitter, and a second comb reflector coupled to the power splitter but not the first comb reflector and not the first delay line. A method comprising receiving an optical signal, splitting the optical signal into a first split optical signal and a second split optical signal, delaying the first split optical signal, tuning the delayed first split optical signal, tuning the second split optical signal, and delaying the tuned second split optical signal.

A method for fabricating a group-III nitride semiconductor laser device stably supplies laser cavity mirrors having a low lasing threshold current through the use of a semi-polar plane. A blade 5g is forced down through a first region ER1 to keep the first region ER1 squeezed between a support member H2 and a movable member H1 together with a part of a protective sheet TF in contact with the first region ER1 while the tension generated in the area of the protective sheet TF in contact with the first region ER1 with the movable member H1 increases until the semi-polar principal surface SF at an end face EG1 of the first region ER1 tilts by a deflection angle THETA from the semi-polar principal surface SF of a second region ER2, and a force is thereby generated in the first region ER1 in a direction opposite to the direction of travel of the blade 5g toward the first region ER1. For example, an angle ALPHA is within the range of 71 degrees to 79 degrees, and the deflection angle THETA is within the range of 11 to 19.

Tensile strained germanium is provided that can be sufficiently strained to provide a nearly direct band gap material or a direct band gap material. Compressively stressed or tensile stressed stressor materials in contact with germanium regions induce uniaxial or biaxial tensile strain in the germanium regions. Stressor materials may include silicon nitride or silicon germanium. The resulting strained germanium structure can be used to emit or detect photons including, for example, generating photons within a resonant cavity to provide a laser.

A semiconductor laser includes a semiconductor nanowire of a first conductivity type provided over a substrate, a light emitting layer provided around the semiconductor nanowire and insulated at an upper end and a lower end thereof, a cladding layer of a second conductivity type different from the first conductivity type, the cladding layer being provided at an outer periphery of the light emitting layer, a first electrode electrically coupled to an end portion of the semiconductor nanowire, a second electrode electrically coupled to an outer periphery of the cladding layer, a first reflection mirror provided at a one-end portion side of the semiconductor nanowire, and a second reflection mirror provided at the other end portion side of the semiconductor nanowire.

A third-order distributed feedback laser has an active medium disposed on a substrate as a linear array of segments having a series of periodically spaced interstices therebetween and a first conductive layer disposed on a surface of the active medium on each of the segments and along a strip from each of the segments to a conductive electrical contact pad for application of current along a path including the active medium. Upon application of a current through the active medium, the active medium functions as an optical waveguide, and there is established an alternating electric field, at a THz frequency, both in the active medium and emerging from the interstices. Spacing of adjacent segments is approximately half of a wavelength of the THz frequency in free space or an odd integral multiple thereof, so that the linear array has a coherence length greater than the length of the linear array.

An optical gain architecture includes a pump source and a pump aperture. The architecture also includes a gain region including a gain element operable to amplify light at a laser wavelength. The gain region is characterized by a first side intersecting an optical path, a second side opposing the first side, a third side adjacent the first and second sides, and a fourth side opposing the third side. The architecture further includes a dichroic section disposed between the pump aperture and the first side of the gain region. The dichroic section is characterized by low reflectance at a pump wavelength and high reflectance at the laser wavelength. The architecture additionally includes a first cladding section proximate to the third side of the gain region and a second cladding section proximate to the fourth side of the gain region.

A fiber coupled semiconductor device and a method of manufacturing of such a device are disclosed. The method provides an improved stability of optical coupling during assembly of the device, whereby a higher optical power levels and higher overall efficiency of the fiber coupled device can be achieved. The improvement is achieved by attaching the optical fiber to a vertical mounting surface of a fiber mount. The platform holding the semiconductor chip and the optical fiber can be mounted onto a spacer mounted on a base. The spacer has an area smaller than the area of the platform, for mechanical decoupling of thermally induced deformation of the base from a deformation of the platform of the semiconductor device. Optionally, attaching the fiber mount to a submount of the semiconductor chip further improves thermal stability of the packaged device.

Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same.

A pulsed smaser includes at least one optical resonator and an optical pump. The at least one optical resonator includes opposing mirrors, a solid state gain medium having a masing frequency in a range of from about 50 GHz to about 1 THz, and a Q-switch, wherein the solid state gain medium and the Q-switch are optically arranged between the opposing mirrors. The optical pump is arranged to provide optical pump power to the solid state gain medium. The optical pump and the Q-switch are configured to generate pulsed masing in the solid state gain medium at the masing frequency at room temperature to provide output electromagnetic radiation at the masing frequency.

A method to tune an emission wavelength of a laser diode (LD) finely is disclosed. The method first controls a temperature of the etalon filter in T1 or T2, where the transmittance of the etalon filter becomes 40 to 50%, assuming a height between the peak and the bottom of the periodic transmittance to be 100%, at the grid wavelength λ1 or λ2, respectively. Then, the temperature of the LD is adjusted such that the intensity of light emitted from the LD and transmitted through the etalon filter becomes 40 to 50%.

A GRINSCH laser having an asymmetric configuration wherein the optical confinement is weighted more to the n-doped multilayer section than to the p-doped multilayer section. The GRINSCH laser can emit laser light at a wavelength λ=976 nm over a broad area with a beam power of 11.4 W at a 12 A bias current at a temperature of 20° C. Fabry-Perot and distributed Bragg reflector GRINSCH laser configurations are disclosed.

Novel methods and systems for miniaturized lasers are described. A photonic crystal is bonded to a silicon-on-insulator wafer. The photonic crystal includes air-holes and can include a waveguide which couples the laser output to a silicon waveguide.

The invention provides a laser converter for converting a laser radiation of shorter wavelength to a laser radiation of longer wavelength using a single stage conversion. The laser converter comprises a laser diode for emitting a laser radiation in a first wavelength range, a cylindrical microlens for transferring and focusing the laser radiation to a laser chip and the laser chip for absorbing the laser radiation and emitting the laser radiation in a second wavelength range.

A device including one or more layers with lateral regions configured to facilitate the transmission of radiation through the layer and lateral regions configured to facilitate current flow through the layer is provided. The layer can comprise a short period superlattice, which includes barriers alternating with wells. In this case, the barriers can include both transparent regions, which are configured to reduce an amount of radiation that is absorbed in the layer, and higher conductive regions, which are configured to keep the voltage drop across the layer within a desired range.

There is provided a surface emitting laser allowing a direction of a far-field pattern (FFP) centroid to be inclined from a normal direction of a substrate providing the surface emitting laser, comprising: a substrate; a lower reflecting mirror, an active layer, an upper reflecting mirror stacked on the substrate; and a surface relief structure located in an upper portion of a light emitting surface of the upper reflecting mirror, the surface relief structure being made of a material allowing at least some beams emitted from the surface emitting laser to be transmitted therethrough, a plurality of regions having a predetermined optical thickness in a normal direction of the substrate being formed in contact with other region in an in-plane direction of the substrate, and a distribution of the optical thickness in the in-plane direction of the substrate is asymmetric to a central axis of the light emitting regions.

Disclosed is an ASE-free continuously tunable external resonator laser in which reduction in tuning range and decrease in output are suppressed. The external resonator laser comprises: a fixed support body which has a half mirror that partially reflects incident light and partially transmits incident light fixed therein; and a rotatory support body which is rotatably supported by the fixed support body by way of a shaft, and which has a laser chip that emits light, a collimator lens that collimates light emitted from the laser chip, and a diffraction grating that diffracts light emitted from the laser chip, fixed therein.

Improved brightness and feedback multi-emitter laser diode modules and methods are provided. A plurality of laser diode emitters emit broad-area light beams in a beam direction. In cross-section, each beam is broad in its slow axis and narrow in its fast axis. Groups of downstream optical components collimate, shape, stack and direct the beams along a light path towards a beam spot (which may be fiber-coupled). After collimating, stacking and directing, the beams are Fourier transformed in the fast-axis through a lens feature having a fast-axis focal length less than about 3 millimeters. In some embodiments, the fast-axis focal length is between about 0.1 and 2.0 millimeters. Astigmatism may be introduced between the fast axis and the slow axis in the beams upstream of the lens feature and in accordance with the fast axis focal length of the lens feature. The emitters may receive feedback including wavelength locking feedback.

A light source for a photonic integrated circuit may comprise a reflection coupling layer formed on a substrate in which an optical waveguide is provided, at least one side of the reflection coupling layer being optically connected to the optical waveguide; an optical mode alignment layer provided on the reflection coupling layer; and/or an upper structure provided on the optical mode alignment layer and including an active layer for generating light and a reflection layer provided on the active layer. A light source for a photonic integrated circuit may comprise a lower reflection layer; an optical waveguide optically connected to the lower reflection layer; an optical mode alignment layer on the lower reflection layer; an active layer on the optical mode alignment layer; and/or an upper reflection layer on the active layer.

A sheet processing apparatus which is capable of improving operability while suppressing an increase in apparatus size. In a front cover insertion mode, an insertion sheet for a front cover is inserted into a bundle of sheets on which images have been formed, and in a rear cover insertion mode, an insertion sheet for a rear cover is inserted into the bundle of sheets. Insertion sheets for the front cover and insertion sheets for the rear cover are set with the same orientation in a manual feed tray 105. An insertion sheet for the front cover stored in the manual feed tray 105 is conveyed to a finisher 500 in one of a face-down state and a face-up state. An insertion sheet for the rear cover stored in the manual feed tray 105 is conveyed to the finisher 500 in the other of the face-down state and the face-up state. The insertion sheets for the front cover and for the rear cover conveyed from the manual feed tray 105 and the sheets on which images have been formed are stacked on the finisher 500.

In a device for cutting to length and feeding spine strips (3) for a case maker (1), a center strip conveying device (30) is provided that advances the spine strip material (5, 6) by the spine width (BS) transverse to the board feed direction (23) in a cyclic fashion. The spine width (BS) can be changed from work cycle to work cycle without accumulating additional waste. This can be realized because the previously required width sizing on the material web is eliminated.

A paper sheet binding die set comprises first and second dies, each having an opposed surface comprising a plurality of tooth portions. The first and second dies face each other such that the first die and the second die are capable of meshing with each other. Each tooth portion of the first die comprises a valley-bottom portion, and a peak-top portion. Each tooth portion of the second die comprises a valley-bottom portion, a peak-top portion, and an inclined-surface portion extending at an incline from the valley-bottom portion to the peak-top portion. The peak-top portion of each of the plurality of tooth portions of the first die has a length so as to cover the inclined-surface portion of the corresponding tooth portion of the second die upon meshing of the first and second dies. The first and second dies pressurize the plurality of stacked paper sheets to bind them together.

An image forming system includes: a ring bookbinding section which perform a ring bookbinding to a bundle of sheets by using a binder provided with a spine portion and a plurality of finger portions; and a judging section, wherein a last page is firstly fed immediately after job initiation and, subsequently after having fed the last page, image formation based on the image data is initiated, when the judging section judges that an image is not formed on the last page, and wherein all of the image data is firstly acquired completely after job initiation, subsequently the last page is fed and formed image thereon, and then image formation of remaining pages is carried out, when the judging section judges that image is formed on the last page.

A drill bit assembly has a bit head and a pin body. The bit head comprises a cutting end, an opposite connecting end with an engagement section, and a feature facing the connecting end. The pin body comprises a tubular body with an axial bore therethrough, a connecting end with an engagement section and a feature facing the connecting end. The drill bit assembly is manufactured by positioning the pin body connecting end with the bit head connecting end such that the pin body and bit head engagement sections overlap with a gap therebetween, and the pin body and bit head features are aligned; injecting a thermoplastic or other connecting material in liquid form between the bit head and pin body engagement sections and into the gap; and solidifying the thermoplastic or other connecting material such that the bit head and pin body are mechanically coupled together at their connecting ends and their features are securely aligned.

A security fastener, for use with a corresponding key, having a channel in a head of the security fastener for receiving the key, the bottom of the channel being profiled wherein the depth of the channel varies along the length of the channel; a key for use with a security fastener; a combination, or a kit of parts, comprising a security fastener; a method of manufacturing a security fastener; and a method of processing an order for a security fastener.

An assembly comprising at least two non-metal components which are fixed to each other using at least one fixing system. The fixing system includes a fixing device with a fixing element which is provided with a head and a rod, and a crimping ring which is in contact with one of the components. A protection device is a part of the fixing system which delimits a cavity for confining gas around a portion of the device comprising the crimping ring. In order to improve the repeatability of the operation for positioning the protection device, a guiding device is provided which includes an assembly element on the portion of the fixing device, and an element for guiding the protection device.

Bushing assemblies include a first tubular end portion, a second tubular end portion, and a middle tubular portion. The middle tubular portion has a longitudinal compressive strength that is less than that of the end portions. In some embodiments, the middle tubular portion is constructed of braided sleeving. Also disclosed are bushing assembly kits, apparatuses that include bushing assemblies, such as aircraft, and associated methods of utilizing bushing assemblies.

A fastener includes a cylindrical shaft, a screw head located at an uppermost portion of the cylindrical shaft and comprising a tool indentation therein, a threaded portion on the cylindrical shaft comprising a plurality of external threads, and a countersinking portion located between the threaded portion and the screw head and comprising a cutting section. The countersink portion is tapered from a first diameter equal to a diameter of the threaded portion to a second diameter that is equal to or larger than a diameter or a maximum width of the screw head. The countersinking portion is configured to form a countersink hole in a receiving material as the fastener is rotated and forced into the receiving material.

Safety apparatuses for objects having at least one nut are disclosed. Contemplated apparatuses comprise a base, one or more nut caps, and one or more electronic sensors configured to acquire data related to a corresponding nut, wheel or tire. In some embodiments, a physical nut rotation indicator that can readily be observed by an operator is included, and a retention wall disposed on the base can operate in conjunction with the physical nut rotation indicator to block a rotation of a nut. Apparatuses are preferably configured to remain stable in harsher environments.

A method for applying compression to a joint includes providing an intramedullary fixation assembly having a proximal screw member positioned at a proximal end of the intramedullary fixation assembly and a lag screw member positioned at a distal end of the intramedullary fixation assembly. Medullary canals are drilled in a first and second bone and the medullary canals are reamed. The proximal screw member is inserted into the first bone and a drill is used create a dorsal hole in the first bone. The lag screw member is slideably coupled to the dorsal hole and to the proximal screw member and into the second medullary canal. A torque is applied to the lag screw member to apply compression to the joint.

A screw with anti-loosening means, which includes a securing element with a ring portion and that can be inserted about a shaft of the screw under a head thereof and, with the screw in a state in which it is screwed on a base, prevents the screw from being turned back counter to a screwing-in direction. The securing element has on the ring portion, on a side facing the surface of the base, at least one projection which can be pressed into the surface when screwing in the screw. The securing element can have an outer circumferential region of the ring portion, with finger-like extensions which, with the securing element in the inserted state, extend along the circumference of the head and under spring-elastic forces of the securing element, contact a surface structure of the body that has an inhibiting action counter to the screwing-in direction. The extensions can have inwardly bent-off end portions which engage over the head, or a circumferential portion thereof protruding radially thereon, on an upper side thereof facing away from the shaft.

Provided is a nut into which a bolt (10) including a male-threaded portion with a male-threaded external diameter d and a male-threaded core diameter d1 is screwed, wherein a bolt insertion side end of a female-threaded portion (21) formed in a nut body (20) is provided with an incompletely threaded female portion (22) that is formed by one to three pitches so that an internal diameter dimension D is larger than (d+d1)/2 and is smaller than the male-threaded external diameter d. Accordingly, even when the bolt is screwed into the nut in the inclination direction, the bolt may be rotated about a contact surface with respect to the incompletely threaded female portion (22), and hence seizing may be prevented.

A showerhead electrode is provided where backside inserts are positioned in backside recesses formed along the backside of the electrode. The backside inserts comprise a tool engaging portion. The tool engaging portion is formed such that the backside insert further comprises one or more lateral shielding portions between the tool engaging portion and the threaded outside diameter to prevent a tool engaged with the tool engaging portion of the backside insert from extending beyond the threaded outside diameter of the insert. Further, the tool engaging portion of the backside insert comprises a plurality of torque-receiving slots arranged about the axis of rotation of the backside insert. The torque-receiving slots are arranged to avoid on-axis rotation of the backside insert via opposing pairs of torque-receiving slots.

A method and apparatus for an insulating cover for fasteners. In one advantageous embodiment, an apparatus comprises a washer and a cover. The washer is capable of receiving a fastener. The cover is capable of being secured to the insulating washer, wherein an insulating volume is created with the cover secured to the washer.

A protrusion anchor assembly is provided that utilizes a plurality of extendable pins to secure the anchor body within a bore in any hard material, such as concrete. The anchor body is rotated within the bore while the pins are simultaneously and gradually extended, carving out a groove or grooves within which the pins can sit. After installation, the device is secured within the bore by tightening a jamb nut against the surface of the concrete wall and in some embodiments placing a security plug within the anchor body to ensure that the pins are held in place. The pins prevent the anchor from being withdrawn because they act as protuberances that catch against the edges of the groove and cannot be drawn past that point.

A device for joining a plastic part to a second part with an insert adapted to thread into the plastic part. The insert includes a longitudinal body with outer threads, a hole in the longitudinal body with female threads, and an annular flange. Protrusions and recesses on the bottom of the annular flange alternate in a radial pattern. The insert is threaded into an opening in the plastic part. The protrusions and recesses of the insert interact with the plastic part to resist over rotation of the insert. The opening in the plastic part may include a hole and a counter bore portion. The counter bore includes protrusions and recesses. The protrusions and recesses alternate in a radial pattern. When the insert is threaded into the opening, the protrusions and recesses of the insert interact with the protrusions and recesses of the plastic part and resist over rotation.

A nut assembly and a holddown assembly using the nut assembly are described, including methods of manufacture and assembly. The nut assembly may include a body portion having first and second openings with an internal wall extending between them. A rotation-inhibiting wall may be included between the first and second openings. A nut portion configured to move axially within the internal wall of the body portion includes structures for co-acting with a rotation-inhibiting wall to limit or prevent rotation of the body portion and the nut portion relative to each other. A nut portion and a body portion extending around the nut portion have limited axial movement relative to each other due to axial engagement between adjacent surfaces on the nut portion and the body portion.

In a mobile terminal having a security function, both convenience and security protection are realized so as to prevent a user from feeling bothersome. A mobile phone has an operation control unit which sets the operation of various functions of the mobile terminal to be unusable at any timing. When a used state determination unit determines that the mobile phone is not in an abnormal state and not left, the operation control unit controls operation of the various functions to maintain usable states.

Panel fasteners, panel assemblies, methods of assembly and installation of panel assemblies and panel fasteners, anchor systems, anchor systems with captive fasteners and assemblies are disclosed.

In a driving circuit, one output circuit has a scanning signal line, a first transistor which controls electrical connection between the scanning signal line and a clock signal line which has a gate connected to a first node, the first node which is at an active potential in a first time period including a time period during which the active potential is output to the scanning signal line, a second transistor which electrically connects the first node and an inactive signal line which has a potential to open the transistor in a second time period other than the first time period, and the second transistor has a gate connected to a second node, wherein the second node has two kinds of timings to be charged for retaining the active potential.

A scanning circuit, comprising first signal lines, second signal lines, third signal lines, a drive unit configured to drive the first signal lines, first buffers configured to drive the second signal lines in accordance with signals of the first signal lines, second buffers configured to drive the third signal lines in accordance with the signals of the first signal lines, and a shift register having a first part to be driven by signals of the second signal lines and a second part to be driven by signals of the third signal lines, wherein the first to third signal lines include two signal lines arranged in parallel to each other and configured to transmit the in-phase signals.

A wearable device has a carrier having an aperture. A device has a USB connection and a protrusion wherein the protrusion is received in the aperture to connect the device to a wristband. The device is a USB type device having athletic functionality. The device may further be configured to receive calibration data such that a measured distance may be converted to a known distance based on athletic activity performed by a user.

A counter includes a buffer unit and a ripple counter. The buffer unit generates at least one least significant signal of a count by buffering at least one clock signal until a termination time point. The ripple counter generates at least one most significant signal of the count by sequentially toggling in response to at least one of the least significant signal. The counter performs multiple data rate counting with enhance operation speed and reduced power consumption.

A reset circuit for Gate Driver on Array, an array substrate and a display is used for increasing reliability and long-term stability of a GOA circuit and thus improving performance of the GOA circuit. The GOA reset circuit includes a first electronic switch circuit (301) connected to an input terminal of a GOA unit of the Gate Driver on Array (INPUT); and a second electronic switch circuit connected to an output terminal of the GOA unit (OUTPUT), wherein the first electronic switch circuit (301) is connected to a low level signal terminal and is switched on to connect the low level signal terminal to a reset terminal of the GOA unit (RESET) when the input terminal of the GOA unit (INPUT) is at a high level; and the second electronic switch circuit (302) is connected to a high level signal terminal and is switched on to connect the high level signal terminal to the reset terminal of the GOA unit (RESET) when the output terminal of the GOA unit (OUTPUT) is at a high level.

An n-bit counter is formed from cascading counter sub-modules. The counter includes combinatorial control logic coupled to a lower order counter sub-module. The control logic is arranged to clock gate at least one higher order counter sub-module dependent on a logical combination of outputs of the lower order counter sub-module and where the control logic uses pipelining to store at least one previous control logic output for use in determining a later control logic output.