I. Technical Field
Embodiments relate generally to visual displays, and more particularly to illuminated input devices that can be selectively or fully illuminated.
II. Background Discussion
Electronic devices are ubiquitous in society and can be found in everything from household appliances to computers. Many electronic devices include visual display elements that can be selectively or fully illuminated by a light source, often through backlighting. For example, many electronic devices include keyboards or keypads that can be backlit to allow a user to interact with the device in low light settings. Other electronic devices may be configured to illuminate an associated keyboard or keypad for purely aesthetic purposes.
While providing an attractive backlight for a user is useful in many electronic devices, much of the aesthetic and practical appeal of a device can quickly be compromised if the light source does not transmit enough light to be adequately perceived by a user. Additionally, the light source required for many visual display elements can quickly drain the power source of the electronic device. This may be a problem, for example, when the electronic device is running on battery power or some other depletable power source. Likewise, uneven or inadequate lighting may further detract from the aesthetic appeal or functional aspects of a device.
Although many designs for providing illuminated visual display elements on electronic and personal devices have generally worked well in the past, there is a desire to provide new and improved designs or techniques that result in even more aesthetically pleasing and power-efficient visual display elements. In particular, the ability to provide visual display elements on electronic and personal devices in a manner that can generate a sufficient amount of light to fulfill a purpose while conserving space and power is desirable.
Methods and apparatuses disclosed herein relate to backlit keyboards and keypads. One embodiment may take the form of a backlit keyboard that includes a light emissive layer having emissive areas that transmit light through the keycap in an upward direction. In some embodiments, the light emissive layer may include an organic light-emitting diode light source. The emissive areas may be formed by depositing light-emitting polymers onto the surface of a substrate layer. In one embodiment, the substrate layer may be transparent or semi-transparent so that light transmitted by the emissive areas is not blocked. In some embodiments, an encapsulation layer may further include a printed circuit layer for transmitting command signals to the processing unit of an electronic device upon actuation of the keycaps.
Some embodiments may take the form a keyboard including at least one keycap, a dome switch layer underlying the keycap, and an encapsulation layer underlying the dome switch layer. The encapsulation layer may include a first printed circuit layer configured to transmit a signal corresponding to the at least one keycap. The keyboard may further include a light emissive layer underlying the encapsulation layer. The light emissive layer may include at least one emissive area corresponding to the at least one keycap and a second printed circuit layer configured to supply a voltage to the at least one emissive area.
Other embodiments may take the form of a method for manufacturing a light emissive layer for illuminating a keyboard. The method may include depositing a light-emitting polymer onto a first layer to form an emissive area and forming a first circuit on a second layer. The first circuit may be configured to transmit a signal corresponding to a keycap. The method may further include forming a second circuit on the first layer. The second circuit may be configured to supply a voltage to the emissive area.
Still other embodiments may take the form of a keyboard including at least one keycap and a light emissive layer underlying the at least one keycap. The light emissive layer may include at least one emissive area covering only a portion of the light emissive layer and corresponding to the at least one keycap. The keyboard may further include a dome switch layer underlying the light emissive layer.
This summary is provided to introduce a selection of concepts in a simplified form that are further described herein. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Other features, details, utilities, and advantages will be apparent from the following more particular written description of various embodiments, as further illustrated in the accompanying drawings and defined in the appended claims.
The use of the same reference numerals in different drawings indicates similar or identical items.
Embodiments described herein relate to light-transmissive and power-efficient input elements. In particular, certain input elements can take the form of a fully or partially backlit keyboard, individual keys, or a keypad. Sample input devices may be used in conjunction with (or form part of) an electronic device, such as a personal computer (including laptop computers, handheld computing devices, and desktops), computers, televisions, media players, mobile telephones, personal digital assistants (PDA), household and commercial appliances, and so on and so forth.
One embodiment may be a backlit key on a keyboard. The key may include a light emissive layer having emissive areas operative to transmit light in an upward direction and through a keycap. In some embodiments, the light emissive layer may include or be coupled to a light source such as an organic light-emitting diode (OLED). One or more emissive areas may be formed by depositing a light-emitting polymer onto the surface of a substrate layer. In one embodiment, the substrate layer may be transparent or semi-transparent so that light transmitted by the emissive areas is not fully blocked. In some embodiments, the keyboard may include an encapsulation layer including a printed circuit layer for transmitting command signals to the processing unit of an electronic device upon actuation of the keycaps.
In one embodiment, the key layer 120 may include a plurality of keycaps 132. One example of a keycap 132 is shown in a cutaway side cross-sectional view in
The term “horizontal” as used herein is defined as a plane parallel to the top outermost surface 131 of the keycaps 132, regardless of its orientation. The term “vertical” refers to a direction perpendicular to the horizontal direction just defined. Terms such as “above,” “below,” “up,” “down,” “bottom,” “top,” “side,” “higher,” “lower,” “upper,” “over,” and “under” are defined with respect to the horizontal plane.
In some embodiments, the keycaps 132 may be inserted through appropriately-sized openings defined in the keyboard housing. In other embodiments, the keycaps may be inserted through openings defined by a key plate provided underneath the keyboard housing. However, in further embodiments, the keycaps 132 may not be extended through openings, but may be part of the keyboard housing. The keycaps 132 may be unattached to one another or connected via a membrane that extends between the keycaps 132.
The dome switch layer 122 may include a flexible membrane 140 and a plurality of dome-shaped protrusions 143 terminating in switches 142 that may be downwardly depressed to contact a first wiring layer 155 (as shown in
In one embodiment, the membrane 140 may be formed from a non-conductive flexible material. For example, the membrane 140 may be formed from a flexible polymeric material, such as rubber or silicone. The switches 142 may be formed from any conductive material, such as a metal or polyester. In some embodiments, the membrane 140 and the switches 142 may be formed from different materials. However, in other embodiments, the membrane 140 and switches 142 may be formed from the same material. For example, in one embodiment, the membrane 140 and switches 142 may both be formed from rubber, with the switch 142 being doped in a metallic substance that conducts electricity.
In some embodiments, the dome switch layer 122 may further include multiple scissor-switches 170 that may be attached to the keycaps 132. In one embodiment, the scissor switches 170 may include two plastic pieces that interlock in a crossed or “scissor”-like fashion. The scissor switches may engage a plunger that depresses the switches 142 toward the first wiring layer 155 to complete the circuit corresponding to the keycap 132. Generally, the scissor-switches may allow for a shorter key travel distance, and may further extend the life span of the keyboard by reducing side-to-side movement of the keycap 132 when depressed. Other embodiments may include a dome switch layer that does not utilize a scissor-switch mechanism.
As shown in
Generally, an OLED is a light-emitting diode having an emissive electroluminescent layer made from an organic compound. Multiple OLEDS may be formed into or on a film of light-emitting polymers. In one embodiment, the OLED panel may be manufactured by depositing or printing the light-emitting polymers onto a substrate layer 145. When connected to a voltage source, the deposited light-emitting polymers may emit light. As will be further discussed below, the light-emitting polymers may be deposited in a predetermined pattern or configuration so as to form an emissive area 149 having a desired pattern or shape. Accordingly, when the light emissive layer 126 is connected to a supply voltage, the OLEDs in the emissive areas 149 and receiving voltage may emit light, while the other portions of the light emissive layer remain unilluminated. Suitable methods for depositing and patterning the light-emitting polymers may include, but are not limited to, organic vapor jet printing, vapor thermal evaporation, laser patterning, and so on and so forth. In one embodiment, the substrate layer 145 may be formed from a transparent or semi-transparent non-conductive or conductive material. In other embodiments, the substrate layer 145 may be formed from an opaque material. The substrate layer may be formed from any suitable material for receiving the light-emitting polymers, including, but not limited to, polyethylene terephthalate, silicon, glass, plastic, or any other suitable substrate.
In one embodiment, the OLED panel may be a passive-matrix OLED. However, in other embodiments, the OLED panel may be an active-matrix OLED. Additionally, the OLED panel may be top light-emitting, bottom light-emitting, or a combination thereof. Further, the emissive areas 149 may be transparent or semi-transparent when lit. However, in other embodiments, the emissive areas 149 may be an fully or partially opaque.
OLED panels may be used in certain circumstances where traditional display devices are unsuitable or encounter issues. OLED panels do not require a backlight to function, and may therefore be much thinner and lighter than backlit light sources, thus resulting in a thinner and lighter keyboard construction. Additionally, a single OLED panel is capable of producing multiple emissive patches as opposed to a single enlarged emissive area. OLED panels further draw a relatively small amount of power for the light produced, and therefore require less power for their operation than many backlit display devices.
As shown in
In one embodiment, the first and second wiring layers 155, 157 may be printed circuits, in which the wires are deposited onto the encapsulation and/or substrate layers 124, 145. In other embodiments, the wires may be etched or embedded into the encapsulation and/or substrate layers 124, 145. As shown in
The first and second wiring layers 155, 157 may have any suitable wire configuration for connecting the OLEDs and/or dome switches 142 when depressed. For example, the first and second wiring layers 155, 157 may include a plurality of wire rows corresponding to each row of the keyboard, as well as a plurality of wires extending in a direction perpendicular to the rows. Other examples may have different configurations. For example, other embodiments may include wire columns corresponding to each column of the keyboard and wires extending in a direction perpendicular to the columns.
As shown in
Another embodiment may further include an optional metal layer that is positioned underneath the light emissive layer 126. One implementation of this embodiment is shown in
In some embodiments, the light emissive layer 126 may be positioned above the dome switch layer 122. One implementation of this embodiment is shown in
As discussed above, the dome switch layer 122 may be positioned underneath the substrate layer 145 of the light emissive layer 126. The dome switch layer 122 may be positioned above the first wiring layer 155, which may be deposited on a metal layer 129 positioned underneath the dome switch layer 122. In some embodiments, the metal layer 129 may be a rigid or semi-rigid sheet that serves to provide structural reinforcement for the keycap 132 and for the light emissive layer 125 when the keycap is depressed. The metal layer 129 may define mounting holes for receiving the scissor-switches 170 that are attached to the keycaps 132.
In contrast to existing keyboards, which include multiple layers obstructing light from the illumination source, the light emissive layer of the described embodiments may be positioned directly underneath the dome switches or on top of the dome switches, thereby enhancing the amount of light transmitted through the keycap. Accordingly, the need for additional light-enhancing features, such as microlenses and masks configured to prevent scattering, is reduced or eliminated. However, other embodiments of keyboards may include additional layers between the light emissive layer 126 and the keycap 132. For example, one embodiment may include a layer positioned above the light emissive layer 126 that includes a microlens array configured to enhance the amount of light emitted from the emissive areas 149.
In some embodiments, the driver 130 may control the light source based on an input from a light sensor. The light sensor may be an ambient light sensor configured to sense light within the visible light spectrum. In one embodiment, the driver 130 may be configured to turn on and turn off the light source based on the amount (or brightness) of light impinging on the light sensor. The driver 130 may further be configured to dim or brighten the light source based on the reading from the light sensor. As an example, the driver may increase the frequency of the PWM signal to brighten the light source if the ambient light sensor indicates that the environment is dark or light is otherwise below a threshold.
Other embodiments may control the light source based on a battery reading, for example, to conserve battery power of the laptop or computer. In one embodiment, the driver 130 may be configured to turn on and turn off the light source based on the amount (or brightness) or level of charge of a battery. The driver 130 may further be configured to dim or brighten the light source based on the level of charge of the battery. As an example, the frequency of the PWM signal may be adjusted to dim the light source and/or turn off the light source if a power meter indicates that the battery is at a low level or otherwise below a threshold.
The processing unit 160 may be within or external to the keyboard. In some embodiments, the processing unit 160 may be a processing unit within the electronic device. For example, the processing unit may be a microprocessor or a central processing unit of a desktop computer or laptop, and the microprocessor or central processing unit may be configured to communicate with the driver 130. For example, the microprocessor may transmit control signals to the driver 130 to turn off, turn on, brighten and/or dim the light source. Alternatively, software or firmware, such as in the form of an operating system, may be configured to control the driver 130. In other embodiments, the processing unit may be provided within the keyboard housing. The processing unit 160 may be connected to the first wiring layer 155, which, as alluded to above, may be deposited on or part of the encapsulation layer 124. As discussed above, the first wiring layer 155 may be configured to transmit command signals corresponding to a depressed keycap to the processing unit 160 for processing the signal associated with the depressed key.
As discussed above, the legends 141 may be etched to allow light to pass through the keycap 132, while the unetched portions of the keycap may be formed from or coated with a light-blocking material to block light emitted by the emissive areas 149. Accordingly, the legends 141 may fully or partially control the amount of light emitted by the keycaps 132, regardless of the shape or size of the emissive area 149 underlying the keycaps. As such, even if a particular emissive area 149 is larger than the area encompassed by the legend 141, a keyboard user may perceive the outline of the legend when the keyboard is illuminated, as opposed to the entire emissive area.
In another embodiment, shown in
The embodiments described in
In operation 505, the method may include forming a second circuit on the first layer. As discussed above, the second circuit may be deposited onto the substrate layer. In one embodiment, the second circuit may be configured to transmit a voltage to the emissive areas of the keyboard. When connected to the voltage, the emissive areas may be illuminated. In operation 507, the method may include aligning at least a portion of the keycap with the emissive pattern along at least one vertical axis so that light transmitted by the emissive pattern is directed through at least a portion of the keycap. In one embodiment, the emissive pattern may be aligned along at least one vertical axis with the legend etched onto the outermost keycap surface, and the emissive pattern may have substantially the same shape as the legend. In another embodiment, the emissive pattern may have substantially the same shape as the top surface of the keycap. In alternate embodiments, the operations illustrated in the flow chart can be performed in a different order than that specified by the flow chart. For example, in one embodiment, forming the first circuit on the second layer may be performed after forming the second circuit on the first layer, and so on and so forth.
Other embodiments may include other configurations of illuminated keyboards or keypads that may be implemented in a variety of electronic devices including, but not limited to: a desktop computer; a portable computing device or mobile phone; remote control; appliance such as a refrigerator, microwave oven, and so on; and any other electronic device. Additionally, other embodiments may utilize other types of backlit visual display elements. For example, in one embodiment, a trackpad may be backlit. The trackpad may include an array of touch-sensitive elements with a corresponding backlight array including a plurality of emissive areas for illuminating locations in which the trackpad is touched by a user. Alternatively, the backlight array may illuminate locations in which the trackpad is not touched. As such, although the description included herein may include some specific embodiments and may be related to particular functions, it should be understood that the embodiments described herein may be implemented in a wide variety of devices and may perform a variety of functions.