Methods and apparatus for conserving battery power in an electronic shelf label system

An electronic shelf label (ESL) system comprising:

• an ESL comprising a display for displaying informational text, a receiver for receiving wireless messages, a battery for providing power, a memory, a switch for applying the power to the receiver from the batter, and control circuitry for controlling operation of the ESL including controlling application and removal of the power by the switch;
• and
• a host computer for wirelessly transmitting a message to the ESL including a time period during which the receiver does not receive any additional messages, and a command to enter a reduced power consumption mode at a beginning of the time period and to leave the reduced power consumption mode at an end of the time period;
• said receiver receiving the message, and said control circuitry storing the time period in the memory, turning off the switch to remove the power from the receiver at the beginning of the time period in accordance with the command while other ESL components remain powered, and turning on the switch at the end of the time period to reapply the power to the receiver and facilitate reception of the additional messages in accordance with the command.

A method of reducing power consumption by a plurality of electronic shelf label (ESLs) comprising the steps of:

• (a) wirelessly receiving messages by receivers in each of the ESLs, wherein the messages include different time periods during which the receivers do not receive any additional messages, and a command to enter a reduced power consumption mode at a beginning of the time periods and to leave the reduced power consumption mode at different ends of the time periods;
• (b) storing the time periods in memories of the ESLs by control circuitries in the ESLs;
• (c) turning off switches in the ESLs at the beginning of the time periods by the control circuitries to remove battery power from the receivers to enter the reduced power consumption mode in accordance with the command while other components in the ESLs remain powered;
• (d) timing the time periods by the control circuitries;
• and
• (e) turning on the switches at the different ends of the time periods by the control circuitries to reapply the battery power to the receivers and facilitate reception of the additional messages in accordance with the command.