Could future iOS devices -- at least some of them -- have two displays? Seems so, as an Apple patent (number 20110080348) involving electronic devices with a primary display and selectively illuminated secondary display have appeared at the US Patent & Trademark Office.

Systems and methods for selectively illuminating a secondary display are provided. An electronic device can include a primary display (e.g., a liquid crystal display (LCD) screen) and a printed segmented electroluminescence (secondary) display. The primary display can be used to convey visual content to a user, and the secondary display can be used to guide a user providing inputs to the device. For example, the secondary display can be selectively illuminated to provide one or more indicators that represent where or how a user can provide inputs to the device. The inventors are Gloria Lin, Andrew Hodge, Taido Nakajima, Bruno Germansderfer and Saumitro Dasgupta.

Here's Apple's background and summary of the invention: "This is directed to electronic devices with displays. In particular, this is directed to systems and methods for selectively illuminating a secondary display integrated in an electronic device.

"Traditional electronic devices include a display for providing visual outputs to a user. For example, a traditional device may include a liquid crystal display (LCD) for providing visual outputs to a user. Some traditional electronic devices may further include a touch interface overlaying the display for receiving inputs from the user. For example, a device may include a touch screen assembly with a display for providing outputs and a corresponding touch interface for receiving user inputs.

"To assist a user in providing inputs, traditional devices use the display to provide indicators to the user regarding where and how to provide a touch input. For example, a traditional device may display a virtual button on a touch screen to indicate that a user can touch that portion of the screen to provide an input. However, providing such indicators occupies space on the touch screen that could otherwise be used for displaying visual content.

"This is directed to systems and methods for selectively illuminating a secondary display. An electronic device can include a primary display (e.g., a liquid crystal display (LCD) screen) and a secondary display (e.g., a printed segmented electroluminescence display). The primary display can be used to convey visual content to a user, and the secondary display can be used to guide a user providing inputs to the device. For example, the secondary display can be selectively illuminated to provide one or more indicators that represent where or how a user can provide inputs to the device.

"A secondary display can include multiple regions, and one or more of the regions can include multiple segments. Different regions of the secondary display may be selectively illuminated to draw a user's attention to those regions or an area adjacent to those regions. For example, a region of a secondary display may be illuminated to draw a user's attention to an adjacent area of a touch screen. Different segments of a secondary display region may also be selectively illuminated to form indicators that convey information to a user. For example, a secondary display can selectively illuminate a subset of segments to form an indicator instructing a user to provide a certain type of input.

"A secondary display may be selectively illuminated based on a determined condition of the electronic device. For example, a device can include a motion sensing component for determining the angle at which the device is held (e.g., portrait orientation or landscape orientation), and the secondary display can be selectively illuminated based on the determined orientation. A determined condition can include any suitable condition of the device, including its orientation (e.g., portrait or landscape), location, operating state, or active software application."

Here's Apple's background and summary of the invention: "An embodiment of the invention relates generally to electronic devices having a camera function (referred to here as an electronic camera device), and more particularly to techniques for controlling the camera flash. Other embodiments are also described.

"In photography, a conventional camera flash is used to improve image picture quality in low light situations, by illuminating the scene with a burst of visible light while a picture of the scene is taken. For portable devices, such as handheld dedicated digital cameras and multifunction devices referred to as smart phones, the practical choices for an integrated, flash light source include the use of light emitting diodes (LEDs) and gas discharge lamps. An LED flash can be used to provide continuous illumination, which provides good illumination for capturing a rapid sequence of images, such as a video sequence. A gas discharge flash is typically operated in a pulsed manner to provide a very high intensity light but for a relatively short duration, no longer than the period of time the shutter is allowed to remain open to capture the scene for a single picture or frame. It is some times desirable to provide a less intense flash, e.g. during a redeye reduction process where the main flash is immediately proceeded by one or more reduced intensity flashes.

"Illumination by flash is provided during the image-framing period (also referred to as the single shutter cycle for taking a picture). A typical range for such a period is 200-300 milliseconds. Some LED flashes are not capable of providing their highest level of illumination for the entire image framing period, and thus have to be pulsed with, for example, one larger pulse and one smaller pulse during the entire shutter cycle. There may also be thermal reasons for pulsing an LED flash.

"In other aspects of photography, it is known that a moving object in the scene, or movement of the camera relative to an object in the scene, causes motion blur. In other words, the object appears blurred in the picture. Shortening the exposure time for taking the picture may reduce such blur, provided the image sensor is sensitive enough to capture a sufficient amount of light from the scene during the shorter exposure time. In another technique known as deblurring, a signal processing operation known as deconvolution can be applied to the picture in order to recover the high frequency or edge details that have been lost in the blurred picture. It has been reported that for an improved deblur operation, rather than leaving the shutter open continuously for the entire exposure duration, the camera shutter is 'fluttered,' i.e. opened and closed rapidly during a single exposure period, in accordance with a binary pseudo-random sequence or code. This flutter effectively changes the inherent filtering effect of the exposure time, in a way that better preserves the high frequency spatial or edge details in the picture, such that the subsequent deconvolution (deblurring) operation can be more easily performed to recover the edge information in the picture. This so-called coded exposure photography technique or flutter shutter technique has been suggested as being extendable to strobe lighting flashes. This coded flash sequence has been suggested to provide a greater ability to control motion sensing.

"An embodiment of the invention is an electronic device having a camera function for taking a picture, where a controller is to command a camera flash to produce two or more multi-value coded pulses of light during a single shutter cycle of the picture. As redefined here, the term 'camera flash' is not limited to elements that produce only visible light pulses; the camera flash can also, or alternatively, produce non-visible light pulses that can be reflected from moving objects in the scene and then detected by an imaging sensor (as a picture of the scene with the moving object). The pulses are said to be 'multi-value coded' in that the amplitudes of at least two of the flash pulses are non-zero and different relative to each other. This variation in the flash pulses inherently embeds useful information into the picture about the motion of an object, which in turn provides an effective mechanism to subsequently deblur the picture (using stored knowledge of the timing and variable amplitude characteristics of the variable flash pulses). The mechanism is also applicable in the case of video compression, to perform motion compensation across several frames of video. Having the amplitude of the flash pulses be variable yields an improved ability to subsequently discriminate the high frequency or edge components of the picture, during the subsequent deblurring or motion compensation operation.

"The above summary does not include an exhaustive list of all aspects of the present invention. It is contemplated that the invention includes all systems and methods that can be practiced from all suitable combinations of the various aspects summarized above, as well as those disclosed in the Detailed Description below and particularly pointed out in the claims filed with the application. Such combinations have particular advantages not specifically recited in the above summary."

-- Dennis Sellers