JPH06265848A - Method and device for display - Google Patents

Abstract

PURPOSE:To adjust a display by a liquid crystal display device and pilot lamps to an optimum display state corresponding to environmental brightness by providing an illuminance sensor which detects the environmental brightness, and decreasing the light emission quantity of a back light and increasing the light emission quantity of the pilot lamps when the degree of the brightness is high. CONSTITUTION:The liquid crystal display device 1 and operation buttons 20 are arranged on the front surface of a casing 10, and the illuminance sensor 2 is arranged on the top surface of the casing 10. The liquid crystal device 1 consists of a liquid crystal display plate 11 and the back light 12 attached on its reverse surface. Further, the pilot lamps 21 are arranged in the casing 10 at parts corresponding to the operation buttons 20. When the environment is dark, the light emission quantity of the back light 12 is maximized and the light emission quantity of the pilot lamps 21 in lighting is minimized. When the environment is more bright than a reference value, the light emission quantities of the back light 12 and pilot lamps 21 are inverted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device including a combination of a liquid crystal display and a display lamp, and can be used as a display device for a water heater, a rice cooker or the like.

[0002]

2. Description of the Related Art A remote control device for a water heater, an operation unit for a rice cooker, and the like are provided with a display device for displaying the operating states of the water heater and the rice cooker. FIG. 12 shows a remote control device (D) for a water heater, which is provided with a semi-transmissive liquid crystal display device (1) on its front surface, and the liquid crystal display device (1) is a liquid crystal display panel. (11) and a backlight (not shown) that illuminates this from the back surface. Further, below the liquid crystal display device (1), operation buttons (20) (20) and display lamps (21) (21) for indicating that the operation is performed are arranged. 20) (20) and indicator lamp (2
1) and (21) correspond separately.

In this device, when the water heater main body (B) starts to operate by operating the operation buttons (20) (20), the hot water temperature and the tap water temperature corresponding to the operation function of the operated operation buttons (20) (20) The operation state of the device and the like are displayed on the liquid crystal display device (1), and the liquid crystal display plate (11) is illuminated with a backlight from the back surface to make it easy to see. In addition, the specific operation button (2
The display lamp (21) corresponding to 0) emits light, and which operation button (20) has been operated is displayed.

However, in the above-mentioned conventional device, a large amount of power is required for the display operation by the liquid crystal display device (1) and the display lamps (21), (21), and the limited power is wasted. there were. In addition, there is a problem that the optimum display cannot be performed according to the brightness of the surroundings. The above problems will be described in more detail.

In the type of supplying power from the water heater main body (B) to the remote control device (D) through the power transmission line (C), the range of the power supply circuit incorporated in the water heater main body (B) is limited. Power is supplied to the remote control device (D). Therefore, the power supplied to the remote control device (D) is limited. In addition, the semi-transmissive liquid crystal display device (1) is designed so that the liquid crystal display plate (11) is illuminated by the backlight as described above in order to ensure the clarity of the display even when the surroundings become dark. It has become. On the other hand, since the display lamps (21) and (21) display a predetermined operating state by turning on and off the display lamps, the display lamps (21 21) The light emission amount of (21) is set as large as possible.

However, the liquid crystal display device has a bright surrounding.
When the display pattern of (1) can be easily recognized, it is not necessary to illuminate the liquid crystal display panel (11) with a backlight. Further, if the lighting of the display lamps (21) and (21) can be recognized even in the dark surroundings even with a small amount of light emission, it is not necessary to strongly emit the display lamps (21) and (21). Therefore, in the above-mentioned conventional one in which the backlight is always turned on regardless of the brightness of the surroundings and the light emission amount of the display lamps (21) (21) is uniformly set to the maximum, even though the surroundings are bright. Electric power is wasted as much as the backlight is maintained in the light emitting state. Therefore, if the above power supply is limited, the display lamp
(21) The amount of light emitted from (21) decreases, and it becomes difficult to recognize the lighting state of the display lamps (21) (21).

Further, in the above-mentioned conventional one, the display lamp (21) (2) is used even when the surroundings are dark and can be easily recognized even by a slight light.
Electric power is wasted as much as 1) causes the light to be emitted constantly. Therefore, when the power supply is limited, the light emission of the backlight is weakened accordingly. From this, in the above-mentioned conventional one, if unnecessary power is consumed for each of the display operations, and if the supplied power is limited,
One of the display lamps (21) (21) or the liquid crystal display tended to be unclear.

The present invention has been made in view of the above points, and relates to "a display method of a display device including a liquid crystal display device (1) of a type of illuminating from the backside with a backlight and a display lamp (21)". At that time, it is necessary to prevent wasteful consumption of electric power and adjust the display by the liquid crystal display device (1) and the display lamps (21) (21) to an optimum display state according to the ambient brightness. It is an issue.

[0009]

[Technical Means] The technical means of the present invention for solving the above-mentioned problem is to provide an illuminance sensor (S) for detecting the ambient brightness, and to determine the degree of brightness detected by the illuminance sensor (S). When it is high, it reduces the amount of light emitted from the backlight as compared to when it is low, and when the degree of brightness is high, it increases the amount of light emitted from the display lamp (21) when it is lit. I did that.

[0010]

The above technical means operates as follows. When the surroundings of the display device, that is, the installation part of the display device becomes bright, the illuminance sensor (S) detects it, which reduces the light emission amount of the backlight that illuminates the liquid crystal display plate (11). . LCD panel (11) when the surroundings are bright
This is because the display pattern displayed on the display is easy to visually recognize even if the illumination is weakened.

On the other hand, when the illuminance sensor (S) detects that the surroundings have become bright, the amount of light emitted from the display lamp (21) is increased, whereby the light emission state of the display lamp (21) is increased. Is easier to recognize.

[0012]

[Effect] The present invention has the following unique effects. Backlight or indicator lamp when lit according to ambient brightness
Since the amount of light emitted from (21) is adjusted, power is wasted as compared to the previously described conventional one in which the backlight is always kept on and the amount of light emitted from the display lamp (21) is maximized. The inconvenience consumed can be prevented. Also, when the surroundings are bright, the power supplied to the display lamp (21) can be increased by the amount that reduces the backlight emission amount, and when the surroundings are dark, the emission amount of the display lamp (21) is reduced. Since the power to be supplied to the backlight can be increased by the amount of the power consumption, a large amount of power can be supplied to the display device side that truly needs the power, and the optimal distribution of the power becomes possible.

[0013]

EXAMPLE Next, an example in which the above-mentioned present invention is applied to a remote control device for a water heater will be described. As shown in FIG. 1, on the front surface of the casing (10), the liquid crystal display device (1) and the operation buttons (20) (20) therebelow are arranged as in the above-mentioned conventional one. An illuminance sensor (S) is arranged on the upper surface of the casing (10). In this embodiment, CdS is used as the illuminance sensor (S).

As shown in FIG. 2, the transflective liquid crystal display device (1) comprises a liquid crystal display plate (11) and a backlight (12) attached to the back surface thereof. Also, in this embodiment,
The operation buttons (20) (20) are made of a translucent material, and the operation buttons (20) (20) are integrally raised from the elastic synthetic resin plate (200) as shown in FIG. It was formed. Further, a switch (22) having an indicator lamp (21) (in this embodiment, a light emitting diode is adopted) is provided in the casing (10) corresponding to the operation buttons (20) (20). Has been done.

The liquid crystal display device (1), the display lamp (21) and the like are electrically wired as shown in FIG. The output of the illuminance sensor (S) is compared with the output of the reference value setter (25) by the comparator (26), and the output of the comparator (26) is the first switch (27) composed of an NPN type transistor. And a second switch (28) composed of a PNP type transistor. And
Switches (22) (22) are provided in the collector circuit of the first switch (27).
A parallel circuit of a group and a fixed resistor (29) is inserted,
A backlight (1) is provided between the parallel circuit and the first switch (27).
2) is inserted. Further, indicator lamps (21) and (21) are connected in series to the switches (22) and (22), respectively.

In this device, the installation space of the remote control device (D) becomes dark and the output of the illuminance sensor (S) is changed to the reference value setting device (2
When it becomes larger than the output of (5), an "H" signal is output from the comparator (26) and the first switch (27) is turned on. Then, the backlight (12) of the liquid crystal display device (1) is energized,
As a result, the liquid crystal display panel (11) is illuminated from the back side to make it easy to see. Further, when a specific operation button (20) is operated and a switch (22) corresponding thereto is energized, a display lamp (21) corresponding to this is turned on. Then, the light of the display lamp (21) can be visually recognized from the outside through the translucent operation button (20), and thereby the specific operated operation button (20) can be identified. .

Next, the surroundings become bright and the backlight (1
When it becomes unnecessary to emit light from 2), the output of the illuminance sensor (S) becomes lower than the reference value set by the reference value setting device (25), and the "L" signal is output from the comparator (26). Then O
The second switch (28) is turned on instead of the first switch (27) in the N state, whereby the backlight (12) is turned on.
Turns off. In this state, the specific operation button (2
When (0) is operated, the corresponding display lamp (21) emits light as described above, but the high potential side of the backlight (12) and the ground are short-circuited by the second switch (28). Since it is in the state, the amount of light emitted from the display lamp (21) is increased as much as the backlight (12) is short-circuited, and visual recognition is facilitated.

The relationship between the light emission amount Y of the backlight (12) and the display lamp (21) and the ambient brightness X is shown in the graph:
It becomes like FIG. That is, when the surroundings are darker than the reference value X1, the light emission amount of the backlight (12) is maximized and the light emission amount of the display lamp (21) when lighted is minimized.
When the surroundings are brighter than the reference value X1, the light emission amounts of the backlight (12) and the display lamp (21) are reversed.

A second embodiment of the present invention is shown in FIGS.
In this case, the light emission amount (line B) of the backlight (12) linearly decreases to a predetermined value as the surrounding becomes brighter, and then turns off. Further, the light emission amount (line L) of the display lamp (21) linearly increases from the minimum value to the vicinity of the maximum value as the surrounding becomes brighter, and then reaches the maximum value.

An electric circuit for realizing the light emission mode of the backlight (12) and the like is constructed as shown in FIG. C
Output of illuminance sensor (S) consisting of dS and reference value setter (25)
Are compared by a comparator (30), and the output of the comparator (30) is applied to a PNP type switching transistor (31). A backlight (12) is inserted in the collector circuit of the switching transistor (31).

The output of the illuminance sensor (S) is amplified by the transistor (32).
Indicator lamps (21) and (21) are inserted in parallel in the emitter circuit of (32). Switches (22) and (22) are connected in series to the high potential side of each display lamp (21). In this case, when the surroundings become darker than the darkness set by the reference value setting device (25), the comparator (30) outputs an “L” signal and the switching transistor (31) is turned on, whereby the
The backlight (12) starts to emit light. Also, illuminance sensor (S)
Since the output of the transistor (32) is amplified by the transistor (32), the emitter current of the transistor (32) increases as the surrounding becomes brighter and the indicator lamp (2) corresponding to the operated switch (22)
The amount of light emitted in 1) increases linearly. When the current flowing through the display lamp (21) increases linearly, the current supplied to the backlight (12) is limited by that amount, and the light emission amount of the backlight (12) decreases.

In the above embodiment, the amount of light emitted from the backlight (12) is changed linearly and simply. However, the maximum amount of light emitted is at the point P (the surrounding is dim) shown in FIG. May be obtained. 9 and 10 show a third embodiment of the present invention. In this one, the backlight (12)
The second embodiment is the same as the above-described second embodiment, except that the light emission amount (line B) of (1) linearly decreases to a predetermined value according to the surrounding brightness. Also, the electric circuit of this third embodiment (FIG. 10) is also
The configuration is similar to that of the second embodiment shown in FIG. 8 except that the comparator 30, the reference value setter 25, and the switching transistor 31 are not provided.

In the first to third embodiments, the light emission amounts of the backlight (12) and the display lamp are changed in various ways depending on the ambient brightness. ) To (e), these backlights (12) and the like may emit light. In the figure (a)
Allows the backlight (12) (line B) to be switched between a lighting state and a non-lighting state, and the light emission amount (line L) of the display lamp (21) can be linearly changed between a predetermined value and a maximum value. It was done like this. (B) is such that the light emission amount (line B) of the backlight (12) can be switched between the maximum value and the minimum value, and the light emission amount (line L) of the display lamp (21) is between a predetermined value and the maximum value. It can be changed linearly.
In (c), the light emission amount (line B) of the backlight (12) is linearly changed from the maximum value to “0”, and the light emission amount (line L) of the display lamp (21) is set to the maximum value and the minimum value. The value can be switched. (D) is the backlight (12)
The amount of light emission (line B) is linearly changed from the maximum value to a predetermined minimum value, and the amount of light emission (line L) of the display lamp (21) can be switched between the maximum value and the minimum value. is there. (E) is such that both the light emission amounts (lines B and L) of the backlight (12) and the display lamp (21) can be switched between the maximum value and the minimum value.

In each of the above embodiments, the display lamps (21) (2
1) is housed in the casing (10) so that the light of the lamp is scattered to the outside through the operation button (20) (having a light-transmitting property), but as shown in FIG. 21) and (21) may be arranged near the operation buttons (20) and (20) on the front surface of the casing (10). Further, in the above embodiment, the case where the present invention is applied to the remote control device (D) of the water heater is illustrated, but the present invention can be applied to the display device of various appliances such as a rice cooker.

[Brief description of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention.

FIG. 2 is a sectional view of an essential part of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of operation buttons.

FIG. 4 is a control circuit diagram of the first embodiment.

FIG. 5 is a perspective view showing a case where the display lamp (21) is arranged near the operation button (20).

FIG. 6 shows the display lamp (21) and the backlight (1) of the first embodiment.
Graph showing the light emission mode of 9)

FIG. 7 shows the display lamp (21) and the backlight (1) of the second embodiment.
Graph showing the light emission mode of 9)

FIG. 8 is an electric circuit diagram of the second embodiment.

FIG. 9 shows the display lamp (21) and backlight (1) of the third embodiment.
Graph showing the light emission mode of 9)

FIG. 10 is an electric circuit diagram of a third embodiment.

FIG. 11 is a graph showing another light emission mode of the display lamp (21) and the backlight (19).

FIG. 12 is an explanatory diagram of a conventional example.

[Explanation of symbols]

 (1) ・ ・ ・ Liquid crystal display device (19) ・ ・ ・ Backlight (21) ・ ・ ・ Display lamp (25) ・ ・ ・ Reference value setting device (26) ・ ・ ・ Comparator

Claims (2)

[Claims] 1. An illuminance sensor (S) for detecting ambient brightness in a display method of a display device comprising a liquid crystal display device (1) and a display lamp (21) of a type in which a back surface is illuminated by a backlight. When the degree of brightness detected by the illuminance sensor (S) is high, the light emission amount of the backlight is reduced as compared with the case where this is low, and when the degree of brightness is high as compared with the case where this is low. The display method is to increase the light emission amount of the display lamp (21) when it is turned on. 2. An illuminance sensor (S) for detecting ambient brightness in a display device comprising a liquid crystal display device (1) and a display lamp (21) (21) of the type of illuminating with a backlight from the back surface.
And the brightness and reference value setting device detected by the illuminance sensor (S)
Provide a comparator (26) that compares the reference value set in (25) and outputs a switching signal when the former brightness becomes less than the latter reference value, and the switching signal is output from the comparator (26) Display device that reduces the amount of light emitted from the display lamp (21) when the lamp is turned on and switches the backlight for the liquid crystal display device (1) to the turned-on state compared to when it is not output. .