Information terminal equipment provided with backlight

• US 6,798,395 B1
• Filed: 06/19/2000
• Issued: 09/28/2004
• Est. Priority Date: 06/22/1999
• Status: Expired due to Term

• Current Assignee: Kyocera Corporation
• Original Assignee: Kyocera Corporation
• Inventors: Yamauchi, Atsushi, Saito, Masayuki
• Primary Examiner(s): Mengistu, Amare
• Assistant Examiner(s): Dharia, Prabodh M.
• Application Number:
  US09/596,463
• Time in Patent Office: 1,562 Days
• Field of Search: 345/102, 345/63, 345/211, 345/170, 350/345, 350/333, 250/205, 250/234, 455/574, 455/566, 455/550, 395/132, 379/21
• US Class Current: 345/102
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: H01H 2219/038 ambient light dependent
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials
• CPC Class Codes: H04M 1/724 User interfaces specially adapted for cordless or mobile telephones

Abstract

An information terminal device comprises a backlight for illuminating a key operation portion or a LCD display portion; an optical sensor portion for detecting lightness of the surroundings; a backlight control for turning on illumination light according to surrounding light for a fixed time after key operation; and an optical sensor control for applying electric power to the optical sensor portion at regular intervals thereby to detect the surrounding light, wherein the application of the electric power to the optical sensor portion is forbidden except when the surrounding light is detected. Further, the backlight control switches, according to the surrounding light when the key operation is performed, control in which both the key operational portion backlight and the LCD backlight are turned on, control in which only the LCD backlight is turned on, and control in which both of the backlights are not turned on.

Claims

1. An information terminal device comprising:

backlight means for illuminating a key operational portion or a LCD display portion;

an optical sensor portion for detecting lightness of the surroundings;

backlight control means for turning on illumination light according to surrounding light for a fixed time after key operation; and

optical sensor power supply control means for applying electric power to said optical sensor portion at regular intervals thereby to detect the surrounding light,

wherein the electric power to said optical sensor portion is only applied during when the surrounding light is detected.

2. An information terminal device comprising:

backlight means for illuminating a key operational portion or a LCD display portion;

an optical sensor portion which is provided adjacently to a terminating LED and detects lightness of the surroundings;

backlight control means for adjusting illumination light according to surrounding light; and

an optical guide which performs terminating display by guiding light of a terminating LED to the outside at the terminating time and guides the surrounding light to said optical sensor at the illumination control time.

3. An information terminal device comprising:

key operational portion backlight means for illuminating a key operational portion;

LCD backlight means for illuminating a LCD display portion;

battery residual amount detecting means for detecting amount of the residual battery; and

backlight control means for adjusting illumination light according to the battery residual amount, wherein both the key operational portion backlight means and the LCD backlight means are turned on when the battery residual amount is equal to or larger than a first predetermined value, both the key operational portion backlight means and the LCD backlight means are turned off when the battery residual amount is smaller than a second predetermined value, wherein the first predetermined value is larger than the second predetermined value, and only the LCD backlight means is turned on when the battery residual amount is equal to or higher than the second predetermined value but lower than the first predetermined value.

4. An information terminal device comprising:

key operational portion backlight means for illuminating a key operational portion;

LCD backlight means for illuminating a LCD display portion;

an optical sensor portion for detecting lightness of the surroundings; and

backlight control means for adjusting illumination light according to the surrounding light;

wherein said backlight control means switches, according to the surrounding light when the key operation is performed, control in which both the key operational portion backlight means and the LCD backlight means are turned off when the surrounding light is equal to or higher than a first level, control in which only the LCD backlight means is turned on when the surrounding light is equal to or higher than a second level but lower than the first level, and control in which all backlight means are turned on when the surrounding light is lower than the second level, wherein the first level represents a greater light than the second level.