An electrical device having a touch screen and a user interface for adjusting the screen brightness

Abstract

The present invention relates to a device having a touch screen and a user interface. An object of the present invention is to specify a device having a touch screen and a user interface for adjusting the screen brightness, which has improved usability. For this purpose, a device (100) having a touch screen (120) is disclosed, which adjusts the brightness (B) of the screen (120) between a first brightness value (Bmax) and a second brightness value (Bmin1) depending on an input from a user via the touch screen (120) in a first mode; and adjusts the brightness (B) of the screen (120) between the first brightness value (Bmax) and a third brightness value (Bmin2) depending on an input from a user via the touch screen (120) in a second mode in which the ambient brightness (U) is higher than a first threshold (U1).

Description

Technical Field

[0001] The present invention relates to a device having a touch screen and a user interface. Background Art

[0002] The display properties of a screen, such as brightness, contrast, sharpness, hue, and other display properties, can often be adjusted by a user.

[0003] Simple and correct adjustment of the display properties of a screen can significantly improve the usability of the device.

[0004] Conventional devices can be set in such a way that a user can select a mode for adjusting the screen brightness, i.e., the screen brightness can be adjusted manually, i.e., independently of the ambient brightness, or the screen brightness can be adjusted automatically (adaptively), i.e., depending on the ambient brightness.

[0005] For example, the automatic (adaptive) adjustment of the screen brightness (e.g., backlight) can be performed incrementally (adjusted according to the change of ambient light), dynamically (adjusted only according to the significant change of ambient light), periodically (adjusted based on a predetermined schedule), or when the device is awakened (adjusted when the device is awakened from the sleep mode).

[0006] Conventional devices are known from DE 199 56 113 A1, DE 60 2005 003 962 T2, and DE 10 2012 016 290A1.

[0007] However, some users find that the adaptive adjustment of the screen brightness causes discomfort because the screen brightness is not under control.

[0008] The disadvantage of manually adjusting the screen brightness is that a large change in the ambient brightness may result in poor visibility of the information displayed on the screen.

[0009] Therefore, an object of the present invention is to provide a device having a touch screen and a user interface for adjusting the screen brightness, which has improved usability. Summary of the Invention

[0010] This object is solved by a device having the features of claim 1. Preferred embodiments are disclosed in the dependent claims.

[0011] According to one aspect of the present invention, there is disclosed an electrical device having a touch screen, which is configured to adjust the brightness of (at least a part of) the screen between a first brightness value and a second brightness value via the touch screen depending on an input from a user in a first mode where the ambient brightness is lower than a threshold; and in a second mode where the ambient brightness is higher than the threshold, adjust the brightness of (at least part of) the screen between the first brightness value and a third brightness value via the touch screen in response to an input from the user, the third brightness value being greater than the second brightness value, and the first brightness value being greater than the third brightness value and greater than the second brightness value. A higher brightness value corresponds to a brighter screen.

[0012] The first brightness value is preferably the maximum brightness (cd / m 2 ) at which the screen can display information. Instead of brightness, other photometric quantities (luminance or the like) can also be used.

[0013] The second brightness value is preferably the minimum brightness (cd / m 2 ) at which the screen can display information. The second brightness value is preferably greater than zero. The third brightness value is preferably the brightness (cd / m 2 ) at which the screen can display information, which is between the first brightness value and the second brightness value.

[0014] Setting the screen using brightness values means that the screen displays information at the maximum brightness corresponding to the brightness value. It should be understood that a large amount of the information displayed does not have the maximum brightness value. In other words, a brightness value between a minimum value and a maximum value (e.g., between 0 and 255 or between 0 and 65536) is assigned to each pixel, and depending on the image information, the relative brightness of the pixel is adjusted. For example, when representing information in a dark room, the brightness value of an individual pixel is close to the minimum value, while when representing information in a brightly lit room, the brightness value of an individual pixel is close to the maximum value. Setting the screen using brightness values means displaying a pixel having the maximum relative brightness value (e.g., 255) at the maximum brightness corresponding to the brightness value. If the screen is operated using a backlight, then this backlight is preferably set to the brightness value.

[0015] According to one embodiment, the device is configured to always adjust the brightness of the screen in the first mode independently of the ambient brightness.

[0016] According to one embodiment, the device is configured to always adjust the brightness of the screen in the first mode independently of the ambient brightness, where the screen brightness continuously increases or decreases depending on an (user's) input value.

[0017] According to one embodiment, the device is configured to adjust the brightness of the screen between the first brightness value and the second brightness value via the touch screen (only) depending on user input but independently of the ambient brightness in a first mode where the ambient brightness is lower than a first threshold.

[0018] According to one embodiment, the device is configured to adjust the brightness of the screen between a first brightness value and a third brightness value independently of the ambient brightness in a second mode.

[0019] According to one embodiment, the device is configured to adjust the brightness of the screen between a first brightness value and a third brightness value independently of the ambient brightness in a second mode, wherein the screen brightness continuously increases or decreases within the range depending on an (user's) input value.

[0020] According to one embodiment, the device is configured to adjust the brightness of the screen between a first brightness value and a third brightness value depending only on user input via a touch screen and independently of the ambient brightness in a second mode where the ambient brightness is higher than a first threshold.

[0021] In other words, the screen brightness is adjusted based on changes between a first brightness value and a third brightness value only based on user input (or a preset value or a stored value based on a previous user input). Thus, the screen brightness can be changed between a third brightness value and a first brightness value only based on user input. However, the third brightness value is determined and thus the ambient brightness indirectly determines how dark the screen brightness can vary.

[0022] According to one embodiment, the third brightness value changes depending on the ambient brightness of the device.

[0023] According to one embodiment, the first brightness value and the second brightness value are preset independently of the ambient brightness of the device.

[0024] According to one embodiment, the brightness of only a part of the screen is adjusted between a first brightness value and a third brightness value based on user input via a touch screen. Preferably, the brightness of the remaining part of the screen is adjusted between a first brightness value and a second brightness value based on user input via a touch screen.

[0025] The shape of the screen is preferably rectangular. The part of the screen where the brightness is adjusted between a first brightness value and a third brightness value is also preferably rectangular. Preferably, the corresponding long sides of the rectangles (of the screen and the part) are perpendicular to each other.

[0026] If the device has more than one screen, the part of the screen where the brightness is adjusted between a first brightness value and a third brightness value can also be displayed on another screen. If the device has more than one screen, the part of the screen where the brightness is adjusted between a first brightness value and a third brightness value can be displayed on a smaller screen.

[0027] If the device has a display screen that extends beyond a planar main surface (e.g., the front surface), then preferably, the part of the display screen where the brightness is adjusted between a first brightness value and a third brightness value is displayed on a side surface of the device where the associated display (part) surface is smaller than the (possibly planar) main surface (front surface).

[0028] According to one embodiment, it is desirable that in a second mode, in a screen portion where the brightness is adjusted between a first brightness value and a third brightness value, a user interface for adjusting the brightness is displayed independently of any user input, while in a first mode, the user interface is hidden depending on any user input.

[0029] Preferably, in the second mode, in a screen portion where the brightness is adjusted between a first brightness value and a third brightness value, a (different) user interface will be displayed to initiate the user interface for adjusting the brightness, regardless of any user input.

[0030] According to one embodiment, it is desirable to set the first brightness value independently of the ambient brightness of the device. According to one embodiment, it is desirable to set the second brightness value independently of the ambient brightness of the device.

[0031] According to one embodiment, it is desirable that in the first mode, the brightness of the screen is adjusted between a first brightness value and a second brightness value via a touch screen only in response to a user input.

[0032] According to one embodiment, it is desirable that in the second mode, the brightness of the screen is adjusted between a first brightness value and a third brightness value via a touch screen only in response to a user input.

[0033] According to one embodiment, it is desirable to set the maximum brightness of the screen specifically depending on a user input.

[0034] According to one embodiment, it is desirable that the brightness value assigned to a specific user input (e.g., the position of a slider) is the same between the first mode and the second mode between the first brightness value and the third brightness value.

[0035] According to one embodiment, it is desirable that the brightness value (between the second brightness value and the third brightness value) assigned to a specific manual user input (e.g., the position of a slider) in the first mode is different from the brightness value (assigned to the same specific manual user input) in the second mode.

[0036] The first brightness value is preferably between 400 and 1500 cd / m 2 and more preferably between 440 and 1000 cd / m 2 and even more preferably between 470 and 900 cd / m 2 and even more preferably between 500 and 800 cd / m 2 and even more preferably between 520 and 700 cd / m 2 and even more preferably between 550 and 600 cd / m 2 and between.

[0037] The second brightness value is preferably between 0.5 and 4 cd / m 2between, more preferably between 0.75 and 3 cd / m 2 between, more preferably between 1.0 and 2.5 cd / m 2 between, more preferably between 1.5 and 2.0 cd / m 2 between, more preferably between 1.6 and 1.9 cd / m 2 between, more preferably between 1.7 and 1.8 cd / m 2 between.

[0038] The third luminance value is preferably between 5 and 50 cd / m 2 between, more preferably between 10 and 40 cd / m 2 between, even more preferably between 12 and 35 cd / m 2 between, even more preferably between 14 and 30 cd / m 2 between, even more preferably between 16 and 25 cd / m 2 between, even more preferably between 18 and 22 cd / m 2 between.

[0039] The maximum extent (diagonal, if applicable) of the screen is preferably between 5 and 150 cm, more preferably between 10 and 100 cm, even more preferably between 12 and 35 cm, even more preferably between 14 and 30 cm, even more preferably between 16 and 25 cm, even more preferably between 18 and 22 cm.

[0040] The (first) threshold of the ambient luminance (determined by a sensor) is preferably between 200 and 100,000 cd / m 2 between, more preferably between 300 and 10,000 cd / m 2 between, even more preferably between 400 and 5,000 cd / m 2 between, even more preferably between 500 and 3,000 cd / m 2 between, even more preferably between 600 and 2,000 cd / m 2 between, even more preferably between 700 and 1,500 cd / m 2 between.

[0041] According to one embodiment, it is desirable that the third luminance value (Bmin2) changes depending on the ambient luminance, wherein the third luminance value (Bmin2) increases as the ambient luminance increases.

[0042] According to one embodiment, if the user manually sets the screen brightness to be lower than a third brightness value (Bmin2), it is desired to set the screen brightness to the third brightness value (Bmin2) only in a part of the screen, while the remaining (part of the) screen does not have to be set to the (very low) brightness value manually set by the user, but is completely deactivated (brightness is zero). This enables energy savings and thus extends the running time of a potentially battery-powered mobile device.

[0043] The ratio (Bmin2 / Bmax) between the third brightness value and the first brightness value may be variable, where the ratio preferably increases as the ambient brightness increases. The gradient of the ratio preferably decreases as the ambient brightness increases. The ratio between the third brightness value and the first brightness value is preferably between 0.2% and 10%, more preferably between 1% and 8% and even more preferably between 2% and 6%. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The present invention is explained in more detail below using exemplary embodiments. The exemplary embodiments show:

[0045] Figure 1 a device according to a first embodiment of the present invention,

[0046] Figure 2 is Figure 1 an enlarged view of the user interface of the device of the embodiment of

[0047] Figure 3 is Figure 1 an enlarged view of the user interface of the device of the embodiment of

[0048] Figure 4 a device according to a second embodiment of the present invention,

[0049] Figure 5 is the relationship between the manual adjustment of the brightness parameter and the screen brightness, and

[0050] Figure 6 is the dependence of the third brightness value (or the ratio of the third brightness value to the first brightness value) on the ambient brightness. DETAILED DESCRIPTION

[0051] Figure 1 shows a device according to a first embodiment of the present invention.

[0052] Device 100 includes a screen 110, which is configured as a touch screen. Device 100 can be configured as a mobile device such as a smart phone. Alternatively, the device can also be a non-mobile device. Device 100 includes a frame 110, but can alternatively be configured as a frameless device. Device 100 includes a control unit, which is not shown, formed by a processor and possibly other components, and controls the brightness of screen 120.

[0053] Device 100 also includes a power on / off switch 210 and volume controls 220, each located on one side of the device outside of screen 120. Switch 210 / controls 220 are designed as physical switches / controls and can thus be operated without touching the screen. User input can thus be made via the power on / off switch 210, volume controls 220, and touch screen 120. In addition to screen 120, the device can also include other display elements such as a screen on the back of device 100 or other display elements such as LEDs.

[0054] Input via touch screen 120 is made via user gestures, such as by pressing one or more fingers in a predetermined area of the screen (touch input) or by dragging a finger across a predetermined area of the screen (drag-and-drop input). Other input options such as via gestures and eyes are possible. The corresponding (possibly only temporarily displayed) area of screen 120 that initiates the input is called the user interface and can be displayed, for example, as soft buttons, icons, or sliders on screen 120.

[0055] Device 100 does not have a physical switch for adjusting the brightness of screen 120, but is configured to allow the user to start a user interface 160 for adjusting the brightness of screen 120 during operation by making a suitable input or selecting (a menu) via touch screen 120 when necessary. In an exemplary embodiment, this user interface 160 is provided by displaying a slider bar 170, a slider 180, and two symbols 190 and 200. Alternatively, user interface 160 can also have a different design. The user can currently make a manual input by holding the slider 180 with one finger and moving the finger across the surface of screen 120. This changes the brightness of screen 120. Specifically, the user can move the slider 180 to a first position (the left edge of slider bar 170 at symbol 190)( Figure 2)The brightness of the screen 120 is set to the minimum adjustable brightness Bmin1. In the same way, the user can set the brightness of the screen 120 to the maximum adjustable brightness Bmax by moving the slider 180 to the second position (the right - hand edge of the slider bar 170 at the symbol 200). Between the first and second positions, the user can continuously (or also in small steps) adjust the brightness of the screen 120 by dragging a finger along the slider bar 170 (and then releasing the finger if necessary), where the brightness continuously increases from the first position to the second position. The manually adjusted brightness value is maintained (stored) (e.g., after releasing the finger) until a new manual adjustment (change) is made.

[0056] The device 100 also has a light sensor 150, which is configured to detect the ambient brightness of the device 100. The control unit of the device is configured to determine the ambient brightness of the device 100 based on the signal of the sensor 150. However, it is not necessarily required to continuously determine the ambient brightness (the determination is possible during operation); alternatively, it is possible to determine the ambient brightness only under certain conditions (possibly periodically).

[0057] Figure 2 and 3 Explain in more detail how to control the brightness of the screen 120 according to the present invention.

[0058] If the ambient brightness U of the device 100 is less than a first limit value U1, for example less than U1 = 1000 cd / m 2 , then the device operates in the first mode. In this first mode, the full range between the minimum adjustable brightness Bmin1 and the maximum adjustable brightness Bmax can be used. In other words, if the ambient brightness is relatively low, i.e., less than the preset limit value U1, then the user can dim the brightness of the screen 120 to the minimum adjustable brightness Bmin1. This allows the user to utilize the full brightness range, while the relatively low ambient brightness ensures that the user can still reliably identify the information displayed on the screen 120. A particular advantage is that the user can define the brightness of the screen 120 and adjust the screen brightness independently of the ambient brightness.

[0059] If the ambient brightness U of the device 100 is greater than the first limit value U1, then the device automatically switches to the second mode, and if the ambient brightness U drops below the first limit value U1 again, then the device automatically switches back to the first mode.

[0060] In the second mode, especially at extremely high ambient brightness, it can no longer be guaranteed that the user will be able to reliably recognize the information displayed on the screen 120, at least when setting the minimum adjustable brightness Bmin1, that is, it can no longer be guaranteed as soon as the slider 180 has been moved to the first position. If the user has set the minimum adjustable brightness Bmin1 in a relatively dark environment, then turns off the device and later turns it on again in an extremely bright environment, then there may specifically be a problem. Then, it may happen that he only notices a black screen and thus can no longer increase the brightness by means of the touch screen 120, which is the only way to adjust the brightness.

[0061] The idea of the present invention is to provide a dedicated quasi-manual adjustment of the brightness, which ensures that the black screen can still be fully recognized at high ambient brightness. For this purpose, it is desired to adjust the range within which the user can manually adjust the brightness depending on the ambient brightness (infinitely). In other words, the brightness value set by the user is actually displayed according to the position of the slider 180 set by the user, as long as reliable detection is ensured. If the limit value U1 ( Figure 3 ) is exceeded, then the brightness of the screen 120 is thus adjusted only according to the (manual) position of the slider 180 set by the user, with the limitation that the brightness value set by the user is equal to or greater than the brightness value Bmin2 determined according to the ambient brightness, and the brightness value Bmin2 is greater than the minimum brightness Bmin1 that can be set. In the remaining range, that is, between the first position (Bmin1) ( Figure 2 ) of the slider 180 and the third position (Bmin2) ( Figure 3 ) of the slider 180, although the slider 180 is actually set to the position specified by the user, as long as the limit value U1 is exceeded, the brightness of the screen 120 is set to the value Bmin2. This is advantageous because in this way the manual input of the user is taken into account (and stored), but reliable recognition is still ensured.

[0062] Once the ambient brightness U is less than the limit value U1, the screen brightness is adjusted from the value Bmin2 to the actual manually set value (which is lower than Bmin2).

[0063] As an alternative to the embodiment mentioned above, in which the slider 180 is always set to the position specified by the user and the brightness is set to the actual manually set value or Bmin2 depending on the ambient brightness, it is possible to change the possible set positions of the slider 180 according to the ambient brightness. In other words, in the second mode, the slider 180 can only move between Bmin2 and the Bmax position, that is, only those brightness values between the corresponding positions of Bmin2 and Bmax on the slider bar 170 can be set. If the user has set the brightness value to be lower than Bmin2 in the first mode and the ambient brightness later increases beyond the limit value U1, then in this alternative, the slider 180 automatically moves to the position corresponding to Bmin2.

[0064] According to a particularly preferred embodiment, in the second mode, if the limit value U1 is exceeded and the manually set brightness value drops below the brightness value Bmin2, then the brightness of the entire screen 120 is not set to Bmin2, but only the part of the screen 120 that displays the user interface 160 for setting the brightness of the screen 120 is set to Bmin2. In other words, in addition to the user interface 160 for adjusting the brightness, it is possible for the user to manually adjust the rest of the screen between the maximum adjustable brightness Bmax and the minimum adjustable brightness Bmin1 regardless of the ambient brightness. Only when the limit value U1 is exceeded is the user interface 160 set to the minimum brightness Bmin2 to ensure that this user interface 160 remains visible regardless of how high the ambient brightness is. Alternatively, only a (different) part can be set to Bmin2 (or higher), and this part (at least partially) contains (displays) the user interface.

[0065] According to another particularly preferred embodiment, it can be stipulated that in the second mode, if the limit value U1 is exceeded and the manually set brightness value drops below the brightness value Bmin2, then the user interface 160 (possibly due to user input or gestures) is even ignored, which then (almost) causes the entire screen 120 to be set to the manually set brightness value below the brightness value Bmin2, whereupon, to ensure higher brightness adjustability, at least one other user interface is displayed at the brightness value Bmin2 (during the operation of the device, except in the standby mode), so that the user interface 160 (which then also has the brightness value Bmin2) can be restarted. In an exemplary embodiment, for example, it is initially possible to display the user interface 160 at least at the brightness value Bmin2 (in the second mode, when the limit value U1 is exceeded and the manually set brightness value drops below the brightness value Bmin2), while the brightness of the remaining screen 120 is set between the maximum adjustable brightness Bmax and the minimum adjustable brightness Bmin1 independently of the ambient brightness - corresponding to the manual setting of the slider 180. If the user hides the (more brightly displayed) user interface, for example, by wiping the user interface 160 away, then at least the status bar 230 is continued to be displayed at the brightness Bmin2, and the user can, for example, display the user interface again via the status bar by wiping the user interface 160 away in the opposite direction, whereupon if the limit value U1 is still exceeded and the manually set brightness value is still below Bmin2, the user interface 160 is continued to be displayed at the brightness Bmin2.

[0066] According to a preferred embodiment, the three values Bmax, Bmin1, and Bmin2 are preset and cannot be changed for a specific device. However, according to another particularly preferred embodiment, the brightness value Bmin2 can be changed depending on the ambient brightness U. According to an example, the screen 120 has a maximum adjustable brightness Bmax of 550.00 cd / m 2 and a minimum adjustable brightness Bmin1 of 2.00 cd / m 2The minimum adjustable brightness Bmin1, where the brightness Bmin2 used as the minimum brightness when exceeding the limit value U1 is, for example, 10.00 cd / m 2 . Of course, the values of Bmax, Bmin1, and Bmin2 can be selected in different ways and are specific to the device. If the brightness value Bmin2 can change depending on the ambient brightness U, then said brightness value can increase with the limit value U1. For example, the brightness value Bmin2 is 15.00 cd / m 2 (instead of 1,000 cd / m 2 ) when the limit value U1 is 10,000 cd / m 2 (instead of 10.00 cd / m 2 ) and is 25.00 cd / m 2 (instead of 1,000 cd / m 2 ) when the limit value U1 is 100,000 cd / m 2 (instead of 10.00 cd / m 2 ).

[0067] Regardless of the different brightness values Bmin2, it is desired to always adjust the brightness value according to the (infinite) manual setting value and only adjust the brightness value to the brightness value Bmin2 when exceeding the limit value U1 and the brightness value drops below the manual setting value. This means that although the user cannot freely set the brightness within the range between Bmax and Bmin1, the manual setting value or alternatively Bmin2 is always used, which prevents the screen brightness from constantly changing with the change of the ambient brightness. According to a preferred embodiment, hysteresis can be provided for switching between the manual setting value and Bmin2 (when switching between the first mode and the second mode), that is, the switch from the first mode to the second mode only occurs when exceeding U1 + ΔU, and the switch from the second mode to the first mode occurs when dropping below U1.

[0068] Figure 4 Shows a device according to the second embodiment.

[0069] Except Figure 1In addition to the functionality described according to the embodiments, it is desirable to provide a switch (or menu) 240 for selecting an operating mode. For example, the user can set the device to a normal operating mode by pressing the switch 240 (touch input). The brightness setting via the user interface 160 is independent of the ambient brightness, i.e., the brightness actually manually set between Bmin1 and Bmax (corresponding to the continuously adjustable position of the slider 180 on the slider bar 170) is always used. Also by pressing the switch 240 (touch input), the device can be reset to an operating state according to the present invention, i.e., the user can choose whether to operate the device in a normal (non-ambient brightness adaptive) operating state or a quasi-non-ambient brightness adaptive operating state (where the actually manually set brightness (corresponding to the continuously adjustable position of the slider 180 on the slider bar 170) is used), but this brightness is adjusted relative to a lower value when the limit value of the ambient brightness is exceeded.

[0070] In addition, it is possible to provide the user with a choice of other operating modes, such as a brightness adaptive operating mode. For example, such an additional operating mode can be activated or selected via an additional switch (touch input). In other words, the device according to the present invention does not necessarily have to continuously perform the inventive brightness control of the (main) screen, but this brightness control can be selected by the user.

[0071] Figure 5 Shows the relationship between the manual adjustment of the user's brightness parameter and the maximum screen brightness.

[0072] On the abscissa, the position x of the slider 180 (on the slider bar 170) that can be adjusted by dragging the user's finger between a first position (X MIN ) and a second position (X MAX ) is shown. Depending on the size of the screen 120, the length of the slider bar 170 can be, for example, between 3 and 25 cm, preferably between 4 and 10 cm.

[0073] It can be seen that the set display brightness B corresponds to the brightness value manually set by the user as long as the ambient brightness U is less than a first limit value U1. In other words, the display brightness B is then completely determined by the user's manual input, i.e., the position of the slider 180 on the slider bar 170. In the case where the ambient brightness U increases, this (manual) determination is maintained for higher brightness values, but for low brightness values of the screen 120, this (manual) determination is maintained at a minimum level (Bmin2) such that the slider 180 required to adjust the screen brightness is still displayed with sufficient contrast. If the ambient brightness U later drops below the limit value U1 again, then the screen brightness is also set below the third brightness value (Bmin2) again according to the manual input. It can be seen that the third brightness value (Bmin2) can be changed for different ambient brightnesses U.

[0074] Figure 6Shows the dependence of the third brightness value (or the ratio of the third brightness value to the first brightness value) on the ambient brightness U, where the ambient brightness is given in lux in the exemplary embodiment of Figure 6 given in lux.

[0075] It can be seen that if the third brightness value (Bmin2) is completely changed for different ambient brightnesses U, the ratio of the third brightness value to the first brightness value is in the range between 1 and 6%. This ensures that, on the one hand, the controller 180 required to adjust the screen brightness still displays at a sufficient contrast to facilitate the user's operation at the corresponding ambient brightness U, and on the other hand, it still fully guarantees the low screen brightness required by the user through manual adjustment. In the case where the third brightness value (Bmin2) changes, preferably, the ratio of the third brightness value to the first brightness value increases as the ambient brightness U increases, but the increment decreases as the ambient brightness U increases.

[0076] List of reference symbols

[0077] 100 Device

[0078] 110 Housing

[0079] 120 Screen

[0080] 130 Microphone

[0081] 140 Speaker

[0082] 150 Light sensor / Camera

[0083] 160 User interface

[0084] 170 Slider bar

[0085] 180 Slider

[0086] 190 Minimum brightness symbol

[0087] 200 Maximum brightness symbol

[0088] 210 On / Off switch

[0089] 220 Volume control

[0090] 230 Status bar

[0091] 240 Switch for selecting the operation mode

Claims

1. A device (100) having a touch screen (120), the device (100) being adapted to a) in a first mode when the ambient brightness (U) is below a first threshold (U1), adjust the brightness (B) of the touch screen (120) between a first minimum adjustable brightness value (Bmin1) and a maximum adjustable brightness value (Bmax) via the touch screen (120) independently of the ambient brightness and depending on the user's input, and b) in a second mode when the ambient brightness (U) is above the first threshold (U1), adjust the brightness (B) of the touch screen (120) between the maximum adjustable brightness value (Bmax) and a second minimum adjustable brightness value (Bmin2) via the touch screen (120) independently of the ambient brightness and depending on the user's input, c) wherein the second minimum adjustable brightness value (Bmin2) is greater than the first minimum adjustable brightness value (Bmin1), and d) wherein the maximum adjustable brightness value (Bmax) is greater than the second minimum adjustable brightness value (Bmin2) and greater than the first minimum adjustable brightness value (Bmin1), wherein the brightness (B) of only a part (160) of the touch screen (120) is adjusted between the maximum adjustable brightness value (Bmax) and the second minimum adjustable brightness value (Bmin2) based on the user's input via the touch screen (120), and wherein the brightness (B) of the remaining touch screen (120) is adjusted between the maximum adjustable brightness value (Bmax) and the first minimum adjustable brightness value (Bmin1) based on the user's input via the touch screen (120).

2. The device according to claim 1, wherein the second minimum adjustable brightness value (Bmin2) changes depending on the ambient brightness (U) of the device (100).

3. The device according to claim 1 or 2, wherein the maximum adjustable brightness value (Bmax) and the first minimum adjustable brightness value (Bmin1) are preset independently of the ambient brightness (U) of the device (100).

4. The device according to claim 1, wherein in the part (160) of the touch screen (120) where the brightness (B) is set between the maximum adjustable brightness value (Bmax) and the second minimum adjustable brightness value (Bmin2), a user interface (170, 180, 190, 200) for setting the brightness is displayed independently of the user's input in the second mode, while the user interface (170, 180, 190, 200) is hidden depending on the user's input in the first mode.

5. The device according to claim 1 or 2, wherein the brightness (B) of the touch screen (120) in the first mode is adjusted specifically between the maximum adjustable brightness value (Bmax) and the first minimum adjustable brightness value (Bmin1) depending on the user's input via the touch screen (120).

6. The device according to claim 1 or 2, wherein the brightness (B) of the touch screen (120) in the second mode is adjusted via the touch screen (120) specifically between the maximum adjustable brightness value (Bmax) and the second minimum adjustable brightness value (Bmin2) depending on a user input.

7. The device according to claim 1 or 2, wherein in each case the maximum brightness (B) of the touch screen (120) is set specifically depending on a user input.

8. The device according to claim 1 or 2, wherein the brightness (B) associated with a specific user input is the same in the first mode and in the second mode between the maximum adjustable brightness value (Bmax) and the second minimum adjustable brightness value (Bmin2).

Images