1. Field of the Invention
The present invention relates to a battery check device, particularly for displaying the continuous change of the state of the power source voltage by means of the light emitting display means.
2. Description of the Prior Art
Until now, two kinds of battery check device provided with light emitting display means such as LED and so on are known. The first is designed so that a pulse generating device which oscillates with the frequency corresponding to the state of the power source voltage, whereby the light emitting display means is driven by means of the pulses coming from the pulse generating means in such a manner that the state of the power source voltage is displayed with the flickering frequency of the light emitting display means. The other one is designed so that a plural number of color light emitting display means are provided, whereby a determined color emitting display means is selected in accordance with the state of the power source voltage in a manner such that the state of the power source voltage is displayed with the displayed color.
However, in accordance with the first type, the state of the power source voltage is displayed with the flickering frequency of the light emitting display means so that it is difficult to grasp the relation between the flickering frequency and the state of the power source voltage, which is disadvantageous. On the other hand, in accordance with the second type, the state of the power source voltage is displayed in a kind of step so that it is impossible to display the continuous change of the state of the power source voltage, which is also disadvantageous.