System and method of wireless power level control of TTL camera flash by radio

Methods and systems to set an amount of light to be emitted by a remote flash device may comprise: a first radio communication device coupled to a camera, a means for a user to set a desired light emission intensity or power emission level which may be perceptible to a first radio communication device, and at least a second radio communication device coupled to a remote flash device. The first radio communication device may transmit at least one radio signal to the second radio communication device which may comprise a power emission level. The at least second radio communication device may send any sequence of data or control signals to a remote flash device which may be representative of the desired light emission intensity or power emission level. The at least second radio communication device may send activation signals to the coupled flash device, followed by allowing a delay interval to elapse, followed by sending quench signals to the coupled flash device.

SUMMARY OF THE INVENTION

In various representative aspects, the present invention includes a radio transmitter coupled to a camera and a radio receiver coupled to a flash device, which may be remote. In accordance with an exemplary embodiment, a system to wirelessly actuate a flash device may comprise: a first radio communication device coupled to a camera and at least a second radio communication device coupled to the remote flash device. Among exemplary embodiments, the first radio communication device may transmit at least one radio signal to the second radio communication device in response to receiving camera communications sent from the camera, a user input, or any combination there of. The second radio communication device may set a delay interval, may send activation signals to the flash device, may send quench signals to the flash device, or any combination there of in response to receiving the at least one radio signal from the first radio communication device.

Elements and steps in the figures may be illustrated for simplicity and clarity and have not necessarily been rendered according to any particular sequence. For example, steps that may be performed concurrently or in different order may be illustrated in the figures to help improve understanding of embodiments of the present invention.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Intro

The present invention may be described herein in terms of functional block components and various processing steps. Such functional blocks may be realized by any number of hardware or software components configured to perform the specific functions and achieve the various results. For example, the present invention may employ various cameras, flash devices, radio transmitters, radio receivers, as well as any software to provide functionality and interconnectivity between such cameras, flash devices, radio transmitters, and radio receivers.

In accordance with various exemplary embodiments, cameras for example, may comprise any of still and/or video graphic devices that may capture images in any manner, for example digitally, by film, or any other manner now known or developed in the future that may benefit from the present invention. The present invention may further employ various flash devices, for example, wireless flash devices, strobe light devices, synchronous flash devices, hardwired flash devices, etc. Exemplary flash devices may comprise a single flash device, a plurality of flash devices, coordinated flash devices, various light frequency flash devices, integral flash devices, and the like. Exemplary flash devices may provide flashes comprising various intensity, duration, timing, color, etc. With respect to radio transmitter and radio receivers, the present invention may employ any now known or future developed transmitter/receiver components, and the radio transmitters and receivers may be configured to operate over a single radio frequency, multiple radio frequencies, as well as any other electromagnetic frequency outside of the typical “radio” band. The transmitter/receiver components may function on any one or combination of wavelength, wave type (square wave, s-wave, etc.), amplitude, modulation, frequency deviation, frequency bandwidth, period, power, range, and any other like electromagnetic wave characteristics. Moreover, the radio transmitter may also comprise radio receiving capabilities and may be termed “radio transceiver” capable of both sending and receiving radio signals, and similarly the radio receiver may also comprise radio transmission capabilities and may be termed “radio transceiver” capable of both receiving and sending radio signals.

Thus, the various components may carry out a variety of functions, and in addition, the present invention may be practiced among any number of general environments, for example, still photography, video graphy, high speed photography, portrait imaging, landscape imaging, etc. The system described may be merely one exemplary application for the invention, and the present invention may employ any number of conventional techniques for coordinating a remote flash device and a camera.

Various representative implementations of the present invention may be applied to any system for a camera to communicate with a remote flash device. Turning now toFIG. 1, in accordance with an exemplary embodiment, the present invention may comprise a first radio communication device120(“transmitter unit”) which may be coupled to a camera108. The transmitter unit120may be coupled to a camera108by electrically connecting to a hot shoe connector110of the camera108. The transmitter may alternately or additionally be coupled to a camera108by electrically connecting to a synchronization connector111or port, or data terminal, or any other portion, connector, surface, circuit, or component of a camera either externally or internally to the camera which may provide indication of the operation of a camera, the settings of a camera, user interaction with a camera, the depression of a camera shutter release button109, or the action of actuating a camera shutter, activating an image acquisition operation of a digital sensor of a camera, or any process, signal, data, data stream, or indication which may characteristically precede an operation or activation of a camera.

A transmitter unit may broadcast radio signals116along typical “radio” band frequencies to communicate with an at least second radio communication device250in response to an activation or process of a camera or in response to an input or user's interaction with the camera108or the transmitter unit120. The radio signals116may effectuate the communication between the camera108and the remote flash device212via the at least second radio communication device250.

Turning now toFIG. 2, in accordance with an exemplary embodiment, an at least second radio communication device250(“receiver unit”) may be coupled with a flash device212. The receiver unit250may be coupled with a flash device using an adaptor cable assembly280which may form an electrical connection between a jack, terminal, port, or connector255of a receiver unit250and the hot shoe connector contacts of a flash device212. A receiver unit250may also comprise a hot shoe connector directly on the exterior of the receiver unit250which may be coupled directly to a flash device212without the need of an adaptor cable assembly280.

Turning now toFIG. 3, in accordance with an exemplary embodiment, a transmitter unit120may comprise externally or internally accessible components such as but not limited to a hot shoe connector321having one or more electrical contacts which may correspond to one or more electrical contacts of a hot shoe connector110of a camera108. The hot shoe connector321may provide also a ground contact used to connect the common electrical ground of a circuit of the transmitter unit120to the common electrical ground of a circuit of a camera108. A synchronization port or connector323may provide similar functional electrical connection between a circuit of a transmitter unit120and a synchronization port111or other port or data connector of a camera108which may provide a signal or signals useful to a transmitter unit120. An antenna325which may extend externally to, internally to, or comprised within the housing of a transmitter unit120may be provided for radiating radio signals into free space. A user feedback indicator326which may comprise one or more indicator lights, alpha and/or numeric display, or a graphical display such as a video display or touch screen type display may be provided to convey status or other useful indications of a transmitter unit120to a user. A user input means327which may comprise one or more buttons, switches, dials, or selectors, which may be analog or digital, as well as may comprise a touch sensitive surface, capacitive sensing surface, or a touch sensitive surface used with a touch sensitive graphical display may be provided which may provide input for powering a transmitter unit120on and off, setting various operating conditions, causing a test activation to occur or performing any other function which may be useful to a user. A selector switch or switches324may be provided which may allow a user to set a radio frequency or transmitting channel or channels which may be used by a transmitter unit120. The function of selector switches324may be combined with or used in place of another user input means327or vise versa.

One or more means may be provided externally to or internally to a transmitter unit120which may be used by a user to indicate a power emission level to a circuitry of a transmitter120. A power emission level may be an indication as to the amount of light a flash device should emit when triggered (also defined in this discussion and in the claims as “light emission intensity”), the power emission level or light emission intensity may be a measure of the amount of light produced by a flash device and thus the amount of light contributed to a subject or scene being photographed upon an activation event or activation sequence of a flash device. Such a means of setting a power emission level may be embodied using one or more potentiometers or dials322, or may be embodied by including an additional functionality of a user input means327or selector switches324.

Turning now toFIG. 4, in accordance with an exemplary embodiment, a receiver unit250may comprise externally or internally accessible components such as but not limited to a connector or port255which may be used to electrically connect a circuitry of a receiver unit to the electrical contacts of a flash device212either directly or via an adaptor cable assembly280. The connector or port255may comprise an electrical contact which may be used to send activation signals to a flash device212, may comprise an electrical contact which may be used to send quench signals to a flash device212, and may comprise an electrical contact which may be used to connect a common ground of a circuit of a receiver unit250to the common ground of a circuit of a flash device212. An antenna454which may extend externally to, internally to, or comprised within the housing of a receiver unit250may be provided for receiving radio signals from free space. A user feedback indicator453which may comprise one or more indicator lights, alpha and/or numeric display, or a graphical display such as a video display or touch screen type display may be provided to convey status or other useful indications of a receiver unit250to a user. A user input means452which may comprise one or more buttons, switches, dials, or selectors, which may be analog or digital, as well as may comprise a touch sensitive surface, capacitive sensing surface, or a touch sensitive surface used with a touch sensitive graphical display may be provided which may provide input for powering a receiver unit250on and off, setting various operating conditions, causing a test activation to occur or performing any other function which may be useful to a user. A user input means452may also allow a user to set a radio frequency or receiving channel or channels which may be used by a receiver unit250.

A receiver unit250may also provide in accordance with an exemplary embodiment a data port, hot shoe connector, or other electrical contacts251which may be used to communicate various settings, parameters, operating modes, activation signals, quench signals, or other useful information to a flash device212. An opening or window456may be provided on the exterior of a receiver unit250which may allow a light signal878to be transmitted from a receiver unit250to a flash device212, or a flash device814.

Turning now toFIG. 5, in accordance with an exemplary embodiment, an adaptor cable assembly280may comprise a jack or plug585which may be a ⅛″ stereo phonographic connector which is electrically connected via wires or conductors584or a cord comprising wires or conductors to a connecting apparatus581which may house a connector582which may provide access to electrical contacts583which may be arranged substantially similar to a hot shoe connector110which may be present on a camera108. The electrical contacts583may correspond to the activation signal contact of a flash device212, the quench signal contact of a flash device212, and the ground contact of a flash device212.

Operation

A flash device212may have the ability to be activated at a certain point in time in response to receiving an activation signal on an activation contact of the flash device. An activation contact may be present on the hot shoe connector of a flash device. An activation signal may be indicated to a flash device by pulling a voltage present on an activation contact of a flash device to a lower voltage, the lower voltage may be at or substantially near ground voltage potential (pulling a “high” voltage to a “low” voltage), this an “activation signal” or “activation signals”. Upon receiving an activation signal, a flash device212may cause a xenon tube, light emitting diode, filament lamp, or other means of producing human visible or human invisible illuminating light (“xenon tube”) to begin emitting illuminating light. A flash device212may also have the ability to be quenched at a certain point in time in response to receiving a quench signal on a quench contact of the flash device. A quench contact may be present on the hot shoe connector of a flash device. A quench signal may be indicated to a flash device by pulling a voltage present on a quench contact of a flash device to a lower voltage, the lower voltage may be at or substantially near ground voltage potential (pulling a “high” voltage to a “low” voltage), this a “quench signal” or “quench signals”. Upon receiving a quench signal, a flash device212may cause a xenon tube to stop emitting illuminating light.

Thus, the interval of time which may pass between an activation signal and a quench signal may be substantially representative of the interval of time during which a xenon tube is producing light and moreover, the interval of time during which a xenon tube is producing light may be substantially representative of the total amount of illuminating light emitted by the xenon tube during the interval. Thus, the interval of time which may pass between an activation signal and a quench signal may be substantially representative of the total amount of illuminating light which may be emitted by a xenon tube of a flash device212.

In accordance with an exemplary embodiment of the present invention, a circuitry of a receiver unit250may be able to cause an activation signal from a receiver unit250which may be perceptible to a flash device212; followed by a substantially specific interval of time; followed by a quench signal from a receiver unit250which may be perceptible to a flash device212; the substantially specific interval of time hereafter a “delay interval”.

In accordance with an exemplary embodiment of the present invention, a user may input a level or setting to a user interface327, selector switch324, or dials322, of a transmitter unit120which may be representative of a desired amount of light to be emitted from a xenon tube of a flash device212when activating the flash device in synchronization with the acquisition of an image or images of a camera108; the desired amount of light to be emitted hereafter a “power emission level”. A user may alternately or additionally input a desired power emission level of a flash device directly to the controls available directly on a camera108if the camera108is able to make the desired power emission level perceptible to a transmitter unit120through any means which may include an electrical signal, electrical signals, or data communication which may be provided between a camera108and a transmitter unit120via electrical contacts of a hot shoe connector110and a hot shoe connector321. It is considered that any means of user input or control which may be perceptible to a transmitter unit120may be used to communicate a desired power emission level between a user and a transmitter unit120.

A transmitter unit120may communicate radio signals116which may include a data or indication of a desired power emission level (hereafter “transmitted emission level”). The data comprised within a transmitted emission level may be any value which may indicate or otherwise be representative of a power emission level, including but not limited to a result of an analog to digital conversion, a value of a data memory which may subsequently be referenced to an interval of time, or may be an explicit exact number of microseconds, milliseconds, or other value explicitly indicating a period of time, or the like. A transmitted emission level or a power emission level may be received by a receiver unit250. In accordance with an exemplary embodiment, a receiver unit250may be able to reference a transmitted emission level to a corresponding delay interval. A delay interval may range from a few microseconds to several milliseconds. It is considered that a delay interval may be shorter, or a delay interval may be longer, depending on the application, environment of use, and characteristics of a particular flash device212being used.

In accordance with an exemplary embodiment, a user may set a power emission level on a transmitter unit120. A user may then activate a shutter of a camera108, the activation may have been caused by a user by the depression of a shutter release button109of a camera108. A camera108may then provide an activation signal via a hot shoe connector110or a synchronization connector111which is perceptible to a transmitter unit120. A transmitter unit120may then read a set power emission level from a dial or may reference a power emission level from a data memory of a transmitter unit120. A transmitter unit120may then transmit a radio signal or radio signals116to which a receiver unit250may be responsive. The transmitted radio signals116may indicate a command to cause a receiver unit to begin sending activation signals to a flash device212, and the radio signals may also comprise a transmitted emission level which may correspond to a power emission level which may have been previously set on a transmitter unit120. Upon reception of the radio signals116, a receiver unit250may send activation signals to a coupled flash device212. The receiver unit may reference the received transmitted emission level to a delay interval. The receiver unit may allow the time duration represented by the delay interval to elapse, and may then send quench signals to a coupled flash device212.

In accordance with an exemplary embodiment, a similar sequence may occur in which a delay interval is transmitted prior to a signal or command to send activation signals to a flash device as follows. A user may set a power emission level on a transmitter unit120. The transmitter unit120may then automatically or in response to an input from a user transmit radio signals116to which a receiver unit250may be responsive. The transmitted radio signals116may comprise a command or data which may indicate a power emission level wherein the transmitted radio signals116do not comprise a command or data that would cause a receiver unit250to send activation signals or quench signals to a coupled flash device212, these radio signals which may comprise a command or data representative of a power emission level which do not comprise a command or data that would cause a receiver unit250to send activation signals or quench signals hereafter “level only signals”. A receiver unit250upon receiving level only signals may store a power emission level comprised within the level only signals to an internal data memory of the receiver unit250. The receiver unit may subsequently reference the stored power emission level to a corresponding delay interval, the corresponding delay interval may be stored to a data memory of a receiver unit, the corresponding delay interval which may be stored to a data memory of a receiver unit hereafter a “stored delay interval”. Some period of time following the transmission and reception of the level only signals, a user may activate a shutter of a camera108, the activation may have been caused by a user by the depression of a shutter release button109of a camera108. A camera108may then provide an activation signal via a hot shoe connector110or a synchronization connector111which is perceptible to a transmitter unit120. A transmitter unit120may then transmit radio signals116, or a second radio signal, to which a receiver unit250may be responsive. The transmitted radio signals116, or a second radio signal, may comprise a command or data that would cause a receiver unit250to send activation signals to a coupled flash device212, followed by allowing a stored delay interval to elapse, followed by the receiver unit250sending quench signals to a coupled flash device212; the transmitted radio signals116which may comprise a command or data that would cause a receiver unit250to send activation signals, followed by allowing a stored interval to elapse, followed by the receiver unit250sending quench signals to a coupled flash212hereafter “activation only signals”.

ADDITIONAL EXEMPLARY EMBODIMENTS

It is considered by the present invention that various improvements and alternate embodiments of the present invention may be useful as follows.

In yet another exemplary embodiment, a plurality of power emission levels may be set by a user to a transmitter unit120wherein the plurality of power emission levels may each correspond to a desired amount of light to be emitted by a plurality of flash devices212. This may be useful in such an example wherein a user has multiple flash devices placed in various locations within an environment and wherein the user desires the individual multiple flash devices to emit different amounts of light for example having one flash device as a main light, another flash device as a fill light, and so on. A plurality of power emission levels may be set by a user by providing multiple dials120or other appropriate means of setting multiple individual power emission levels via a user interface such as a video, graphical, alpha and/or numeric display together with an appropriate input means. The plurality of power emission levels may be transmitted by a transmitter unit120via radio signals116individually, sequentially, or together in a single transmission or radio data packet. The plurality of power emission levels may be transmitted together with a signal or data which may cause a receiver unit to immediate begin sending activation signals to a coupled flash device212, or the plurality of power emission levels may be transmitted as level only signals. In accordance with the stated embodiment, a receiver unit250may provide a means of allowing a user to select which of the plurality of power emission levels to which the individual receiver unit250should be responsive. This setting of the desired individual power emission level of the plurality of power emission levels may be made via selector switches452or other appropriate user interface of a receiver unit250.

In yet another exemplary embodiment, a transmitter unit120may provide a “dead band” near the low set point of dials322. When a user adjusts a power emission level below a given level, a transmitter unit120may communicate a value for a transmitted emission level which a receiver unit250may interpret as a zero level, or a level at which no activation signals and no quench signals will be sent to a coupled flash device212. Thus when a user sets a power emission level below a given value, the setting has the effect of causing a flash device212to not emit any light when a camera is activated by a user. This may allow a user to individually disable a flash device which may used along with a plurality of other flash devices and thus the user has the ability to remotely enable or disable a certain flash device or flash devices. It is considered by the present invention that the stated dead band functionality additionally may be enabled or disabled by a user via any of the various user input controls discussed such that a user not desiring the functionality of being able to disable flash devices does not inadvertently disable flash devices when attempting to set flash devices to low power emission level settings.

In yet another exemplary embodiment, a receiver unit may instead of referencing a transmitted emission level or level only signals to a delay interval or a stored delay interval, may instead reference the transmitted emission level to a binary coded instruction which may be representative of an amount of illuminating light that should be produced by a flash device or may be representative of a command which may cause a flash device to carry out another useful function. The binary coded instruction may be communicated between a receiver unit250and a flash device212via various connectors or electrical contacts such as a data port251which may comprise a modular port such as a commercially available RJ-11 type port, a hot shoe connector present on a receiver unit which may provide electrical contacts corresponding to electrical contacts present on a flash device, or the like, a connector or jack255, as well as via a light signal which may be pulsed or modulated so as to convey a binary pattern. As illustrated inFIG. 8, a sophisticated flash device814which may be similar to a flash device212may provide a light sensor815which may be responsive to binary coded pulses of light878which may be on a human visible or human invisible light spectrum. A material which blocks or attenuates light879may be placed around a light transmission window456of a receiver unit250and a light sensor window815of a sophisticated flash device814and may be placed between a receiver unit250and a sophisticated flash device814, the material879may be useful in reducing the amount of light present in an environment from entering a light sensor window815. Some sophisticated flash devices814may have the ability to activate a xenon tube only when light above a given intensity is sensed through a sensor window815; in such case a delay interval may also correspond to a duration of time a constant light signal878or rapidly pulsed light signal is illuminated from a receiver unit in which case a sophisticated flash device814may cause the production of light from a xenon tube substantially near the start of the emission of a constant light signal878and may stop the production of light from a xenon tube substantially near the end of the emission of the constant light signal878.

Mode of Manufacture—Transmitter

A discussion is provided detailing the best mode of manufacture in accordance with an exemplary embodiment of the present invention. It will be clear to one skilled in the art that any number of various substitutions and variations are possible in the actual construction of the present invention. The following discussion and illustrative schematics may not provide every individual component required for manufacture of the present invention. Any components which may have been omitted will be obvious as to requirement, arrangement, part selection, and use to one skilled in the art of electronic circuit design, analog and digital circuitry, printed circuit board design, microprocessors, and the use of various radio transmission and radio reception components and circuitry. Various components omitted from the provided discussion have been done so for simplicity and clarity and may include various resistors, capacitors, inductors, filters, regulators, isolators, and so on, among others.

The following discussion may be more clearly understood by referencing the internal layout illustrations provided inFIG. 6andFIG. 7, as well as the simplified schematic illustrations provided inFIG. 9andFIG. 10, as well as the simplified operational flow charts provided inFIG. 11andFIG. 12.

A transmitter unit120may comprise an exterior housing628which may be made of plastic, metal, or other appropriate material, and may comprise a printed circuit board629(hereafter “PCB”) to which the various other components and circuitry of the transmitter unit may be physically and electrically connected as appropriate.

When a battery630is inserted in a transmitter unit120it may provide the circuit a voltage supply which may be approximately 3 volts (or other voltage as required or as appropriate) which may energize a main power supply header which may provide power to a microprocessor (hereafter “MCU”)631, a radio transmitter module632, the bank of control dials322, and a pull-up voltage to input signal connectors323,321,327. A CR123 size battery may be used as it is readily available, is fairly low cost and may provide 3 volts required for operation without needing a voltage regulator, has high capacity (>1200 mAh) is small in size, and is commonly used for other photography field products including flash units and consumer digital cameras and thus should be available in most consumer stores and camera shops in most countries. It is considered that any power or voltage source may be used which may adequately power the circuitry of the device including but not limited to various rechargeable batteries.

The MCU631, may be a PIC16F677 available commercially from Microchip Corp. An alternate microprocessor, the PIC16F882, also from Microchip is 28-pin and may be used if additional I/O pins are desired for the desired configuration. Each of these suggested MCU parts may include internal high speed clock oscillators and may require minimal external components such as bypass filtering capacitor937between the power supply and ground pins to operate; no external crystals or resonators may be required though in certain variations an external crystal or resonator may be desired or beneficial. The suggested MCU parts include a Serial Peripheral Interface (“SPI”)941which may be a dedicated hardware interface capable of communicating data between various components at high speed and may be used to configure and operate the radio transmitter module632.

The MCU631may be connected to a radio transmitter module632, which may be a CC2500 available commercially from Texas Instruments. The model CC2500 may operate in the 2.4 Ghz radio band and may be compatible with other wireless radio protocols such as but not limited to Bluetooth, ZigBee and WiFi protocols. It may be possible for the described embodiment to communicate with or otherwise participate in various wireless networks of these or similar protocols. A CC1101, also available commercially from Texas Instruments may be used together with or in place of the stated CC2500. The CC1101 may operate in radio bands under 1 Ghz and may be compatible with operation in 900 Mhz ISM bands in North America as well as may be programmed for 869 Mhz band used for ISM in Europe, and the lower frequency of 900 Mhz compared to 2.4 Ghz has greater range and less signal loss through free space and objects compared to the higher frequency 2.4 GHz. A crystal936is provided as an accurate reference intermediate frequency used to synthesize the desired radio frequency. The radio module632may be connected to an antenna325directly or via various additional filtering, tuning, balun networks or other circuitry tuned to the desired radio frequency band.

A bank of control dials322may include standard analog trimming potentiometers (commonly called trimmer pots). A high resistance may be used on the pots to minimize current leakage as they may simply exist to provide an analog voltage reference to an MCU631. Ranges of 1 Megohm to 50 Megohms should be fine with higher numbers resulting in less current leakage but may provide slightly less accurate readings and require longer times to complete analog to digital conversions when an MCU631is reading the pots. The outputs may be connected to pins of the MCU631that are capable of performing analog to digital conversions (“ADC”).

It is considered by the present invention that various methods may be used to provide a user a means of setting a power emission level using any control that is rotary (“rotary control”), as a rotary adjustment may be the most direct and may be the most intuitive method for a user to indicate a power emission level to a device such as a transmitter unit. The rotary control may or may not include clicks or detents, the rotary control may have stops at either end to limit the rotation of a rotary control to one revolution or a portion of a single revolution, or the rotary control may spin freely in continual rotations. The rotary control may provide a knob, a thumb dial, or any other configuration which provides a manipulator or movable surface to a user which when manipulated by a user causes the rotation of a shaft or collar comprised within a rotary control or mechanically connected to a rotary control wherein the position or rotation of a shaft or collar may be used as an indication of a user's desired set point, such that the user's desired set point allows a desired light intensity level of a flash device or power emission level to be set or otherwise indicated by a user to a transmitter unit capable of transmitting any example of radio signals comprising a signal or data representing a setting of a rotary control which may be representative of a user's desired amount of illuminating light to be emitted from a flash device, such that a receiver unit or receiving device capable of receiving any example of a radio signal or radio signals may be capable of causing a flash device to emit an amount of illuminating light substantially corresponding to the user's desired amount of illuminating light that may have been set using a rotary control which may be comprised within or otherwise electrically connected to a transmitter unit which may be further coupled to a camera.

A bank of control switches324may be powered by the main voltage rail via pull-up resistors which have outputs to input pins on an MCU631and may be used to set various parameters desired by the user such as the desired radio frequency to transmit on. The control switches may be common dip switch type devices common on various PCB designs and computer circuit board designs.

The main voltage rail may power a pull-up resistor935, the output of which may be electrically connected to an input pin of an MCU631and a jack323which may be used for connection to a synchronization connector111of a camera, and may also be connected to an electrical contact of a hot shoe connector321and optionally a test activation button or switch327. The voltage allowed through pull-up resistor935may remain high at an MCU631until an activation signal is received from a camera108which may indicating the opening of a shutter of the camera108, at which time the input to an MCU631may be pulled low and may cause a software interrupt within an MCU631which may cause the transmitter unit to begin an activation sequence. Using this configuration, either input323,321, or327can be pulled low to activate the transmitter unit while requiring only one pin on an MCU631as an input. A typical value for a pull-up resistor935is 10 k ohm, though other values may be used.

Contacts633may be provided via a modular connector or simply as exposed pads on the PCB which may be electrically connected to appropriate pins of an MCU631and may be used as an in-circuit-serial-programming (“ICSP”) connector. A similar arrangement of contacts633may provide electrical connection to a J-Tag or similar port which may be provide for similar function on various MCU parts which may be commercially available from other manufacturers. Contacts633may be easily physically contacted for reprogramming and updating of the firmware or operating software executed by an MCU631by the manufacturer using an external chip programmer (not pictured) at any time after initial unit manufacturing.

Mode of Manufacture—Receiver

A receiver unit250may be similar to a transmitter unit120with a few changes as explained in the following discussion. When a battery759is inserted in a receiver unit250which may be a CR123 battery, a main power header may be powered which may provide power to an MCU760, a radio receiver module761, a transistor1070and capacitor1071circuit which may power a light signal source62which may be a visible spectrum or infrared spectrum light emitting diode (“LED”).

An MCU760, which may be a PIC16F882 available commercially from Microchip may be electrically connected1076to a radio receiver module761such as a Texas Instruments CC2500 or CC1101. The electrical connection between an MCU760and a radio receiver module761may comprise a SPI interface. The radio receiver module761may be connected to an antenna454directly or via various additional filtering, tuning, balun networks or other circuitry tuned to the desired radio frequency band, such that the radio receiver module761may be able to receive radio signals116on an appropriate frequency that may be transmitted by a transmitter unit120.

A bank of control switches452may be powered by the main voltage rail, the control switches452may have outputs to input pins on an MCU760and may be used to set various parameters desired by a user which may include the desired radio frequency or channel to receive on, and may include a setting as to whether to send activation signals and/or quench signals via an electrical port251, via an adaptor cable assembly using jack255, via a light signal output means762, and may include a setting as to which of a plurality of power emission levels to be responsive, and so on.

A port, connector, or jack255may be provided as a means to send activation signals and/or quench signals to a coupled flash device212either directly or via an adaptor cable assembly280. A commonly available stereo phonographic jack such as a ⅛″ stereo jack (hereafter “jack”) which may include three conductor contacts may be used. Such a jack may provide an electrical connection to connect a common electrical ground of a circuit of a receiver unit250to the common electrical ground of a circuit of a flash device212, and may provide an electrical connection to send activation signals, and may provide an electrical connection to send quench signals.

A first conductor pin of jack255corresponding to the tip of a male modular ⅛″ stereo connector585may be electrically connected to the collector of an NPN transistor1069, and a second conductor pin jack255corresponding to middle conductor of a modular ⅛″ stereo connector585may be electrically connected to the collector of an NPN transistor1075. The first conductor pin and second conductor pin of jack255may be used to effectuate the sending of activation signals and quench signals to a coupled flash device. A third conductor pin of jack255corresponding to the collar of a male modular ⅛″ stereo connector585may be electrically connected to a common ground of a circuit of a receiver unit250.

On each of the signal lines electrically connected to a jack255, NPN transistors1069and1075may be tied to ground via the emitter of each NPN transistor1069and1075. An MCU760may be electrically connected via a resistor on each signal line to the base of each NPN transistor1069and1075. Diodes1074may be provided on each signal line to prevent potentially high voltage present as trigger voltage on a coupled flash device from reaching back to the MCU760and potentially damaging the receiver unit. An MCU760may force an output to the base of a given the transistor1069or1075high, and some current may flow from the base to the emitter of a transistor1069or1075causing it to allow current to flow from the collector to the emitter which may effectively cause a high voltage being supplied by a coupled flash device to a lower voltage or a voltage substantially near ground which may cause an coupled flash device to activate or quench as appropriate. This arrangement may be desirable as standard transistors may hold higher collector-emitter voltage (which may be in excess of 300 volts) than most flash devices are likely to present, and requires few inexpensive components. An example transistor may be a KSP44/45 available commercially from Fairchild Semiconductor.

A third NPN transistor1070may be used to turn on and off an electrical current through an LED762which may be supplied via a resistor1072and a capacitor1071. A transistor1070may not be required to be rated for high voltages, and it may be advantageous for a transistor1070to have a fast switching time which may be shorter than 1 microsecond. A transistor1070may be a MMBT4401 available commercially from Fairchild Semiconductor. An MCU760may be electrically connected to the base of a transistor1070via a resistor. Causing an MCU760to place a high voltage on transistor1070may cause an LED762to begin emitting light and placing a low voltage on transistor1070may cause an LED762to stop emitting light.

The pins of a data port251may be each electrically connected to individual pins of an MCU760, the pins of an MCU760may be configurable to perform any of multiple potentially useful functions. Examples of useful functions may include capability of being set as inputs or outputs via a software program of an MCU760, capability of being configured individually or collectively as a data port such as a SPI port, a parallel port, a serial port, a differential signaling port, pins that may sense or convert analog voltages to digital data values, pins that may create or set a desired analog output voltage, or provide a clock signal or synchronous clock which may be used together with the transfer of data or other signals, and the like. The pins of a data port251do not necessarily need to be directly electrically connected to an MCU760as in some examples it may be desirable to pass the signal lines through various intermediate components which may include filtering components, electrical isolation components which may include opto-isolators, or other useful circuitry such as but not limited to digital potentiometers, digital to analog converters, and the like.

Thus it may be possible for a data port251to pass electrical signals, indicators, voltages, or data between a flash device212and a circuitry of a receiver unit250, and/or between a circuitry of a receiver unit250and a flash device212such that any of many possible settings, status, or function may be set or activated of a flash device, which may include a desired amount of light a xenon tube should produce when activated which may correspond to a power emission level which may be set by a user on a transmitter unit120.

Detailed Explanation of Exemplary Operational Sequence

A simplified operational flow chart in accordance with an exemplary embodiment of a transmitter unit120is illustrated inFIG. 11and may be described as follows.

A transmitter unit120may power on upon the insertion of a battery power source at step1101. An MCU631may configure a radio module632via SPI interface941,1103, and may cause a radio module632to enter a low power or sleep state1104. An MCU631may then configure itself to wake on an interrupt which may be caused by a falling edge of a signal input means323,321,327and may then enter a low power or sleep state1105.

When a user activates a camera shutter button109, a camera108may pull low the voltage provided by a transmitter unit120via a contact present on a camera hot shoe110or synchronization connector111. This may cause an interrupt1106which may wake an MCU631from a sleep state. An MCU631may immediately wake the a radio module632via SPI941. (Alternately a transmitter module632may have been left in a more readied or more awake state but not broadcasting any radio signals116during step1106, which may decrease the duration of time required for a transmitter module632to begin transmitting radio signals116). An MCU631may then immediately instruct a transmitter module632to begin transmitting radio signals which may include a preamble, channel qualifier, and any other packet over-head which may indicate to a receiver unit250that a valid radio packet is present and should be demodulated or received at step1107.

While a transmitter module632may be busy transmitting a preamble and/or a channel qualifier, an MCU631may perform an analog to digital conversion on one or more voltages which may be present on one or more potentiometers or dials322at step1108. The an MCU631may derive one or more representative 8-bit data which may correspond to a voltage present on one or more potentiometer or dial322, the one or more 8-bit data may be one or more power emission levels. The power emission levels which may each be represented as a single data byte which may be comprised of 8 data bits, may be sent to a data output first-in-first-out (“FIFO”) buffer of a transmitter module632via a SPI941at step1109. Once a transmitter module632completes sending a preamble and/or channel qualifier, the transmitter module632may automatically transmit one or more power emission levels from a FIFO buffer via radio signals116by transmitting the data byte values of the one or more power emission levels digitally by modulating a radio carrier signal using the an appropriate modulation standard or protocol at step1112.

After the one or more power emission levels have been transmitted in step1112, an MCU631may again instruct a transmitter module632to stop transmitting and resume a low power state at step1113. An MCU631may then loop back to the start of the program at step1114,1102, and may again configure itself to wake on an interrupt which may be caused by the falling edge of a signal input means and may then go back to sleep at1105.

A simplified operational flow chart in accordance with an exemplary embodiment of a receiver unit250is illustrated inFIG. 12and may be described as follows.

A receiver unit250may be powered on upon the insertion of a battery power source1201. An MCU760may configure a receiver module761via SPI1076at step1203, and may then instruct a receiver module761to begin actively receiving radio signals and to being looking for any demodulated radio signal to match an expected preamble and/or channel qualifier which may represent a true and valid incoming signal (“valid signal”) which may originate from a transmitter unit120. An MCU760may then instruct a receiver module761to transition an output pin to cause an interrupt in the event that a valid signal is identified at step1203. An MCU760may then configure itself to wake on an interrupt caused by the transition of the pin of a receiver unit761which may occur in response to the identification of a valid signal, and an MCU760may then enter a low power or sleep condition at step1204.

An MCU760may then wait for an interrupt which may be in response to an incoming valid signal at step1205. Upon an interrupt, an MCU760may wake from sleep or a low power condition at step1206and may begin reading received data values from a FIFO buffer of a receiver module761via SPI1076. If a plurality of power emission levels or transmitter emission levels may be expected within a plurality of received data values, a receiver unit250may only process a given data value which may correspond to a power emission level the receiver unit250is intended to act upon, and may disregard other data values.

An MCU760may then correlate a power emission level or transmitted emission level data value to a period of time which may represent a delay interval at step1207. A power emission level or transmitted emission level may be related to a given period of time which may represent a delay interval via a reference table that may be stored in a data memory of an MCU760or hard coded as a portion of operational firmware of an MCU760.

An MCU760may then cause a high voltage on transistor1069which may cause activation signals to be sent to a coupled flash device212. An MCU760may then allow a delay interval to elapse. An MCU760may then cause a high voltage on a transistor1075which may cause quench signals to be sent to a coupled flash device212. This sequence illustrated at step1208. The sequence of sending activation signals followed by allowing a delay interval to elapse followed by sending quench signals may be termed together a “TTL signal” or “TTL signals”.

In accordance with an alternate exemplary embodiment of the present invention, during step1208(or similar step if the discussed sequence of events is altered in any way, or any other step which may or may not be illustrated inFIG. 11orFIG. 12, or any other step or sequence that may be carried out by any exemplary embodiment or similar embodiment of the present invention), an MCU760may send any sequence of data or control signals to any example of a flash device electrically via a data port251or optically via constant, pulsed, digital, or other various coded light signals878which may be emitted by an LED762wherein the any sequence of data or control signals may or may not cause a flash device to emit light or initiate an event of being activated, and wherein the any sequence of data or control signals may or may not set an internal function of a flash device, and wherein the any sequence of data or control signals may or may not indicate to a flash device the amount of light that should be emitted by a xenon tube during an event of being activated. Moreover it is considered by the present invention that the any data or control signals may substantially correspond to a power emission level which may have been set by a user on a transmitter unit120via a rotary control or other means of user input.

An MCU760may then instruct a receiver module761to flush any contents of data remaining a FIFO register of the receiver module761at step1209. An MCU760may then loop back to the start of the operational sequence1210,1202.

SUMMARY

In the foregoing specification, the invention has been described with reference to specific exemplary embodiments. Various modifications and changes may be made, however, without departing from the scope of the present invention as set forth in the claims. The specification and figures may be illustrative, rather than restrictive, and modifications may be intended to be included within the scope of the present invention. Accordingly, the scope of the invention should be determined by the claims and their legal equivalents rather than by merely the examples described.

For example, the steps recited in any method or process claims may be executed in any order and may be not limited to the specific order presented in the claims. Additionally, the components and/or elements recited in any apparatus claims may be assembled or otherwise operationally configured in a variety of permutations and may be accordingly not limited to the specific configuration recited in the claims.

As used herein, the terms “comprise”, “comprises”, “comprising”, “have”, “has”, “having”, “including”, “includes”, “employs”, “employing” or any variation thereof, may be intended to reference a non-exclusive inclusion, such that a process, method, article, composition or apparatus that comprises a list of elements does not include only those elements recited, but may also include other elements not expressly listed or inherent to such process, method, article, composition or apparatus. Other combinations and/or modifications of the above-described structures, arrangements, applications, proportions, elements, materials or components used in the practice of the present invention, in addition to those not specifically recited, may be varied or otherwise particularly adapted to specific environments, manufacturing specifications, design parameters or other operating requirements without departing from the general principles of the same.