# US 8,541,955 B2 · Discharge lamp lighting device, projector, and discharge lamp lighting device control method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,541,955 B2 - Document ID: US8541955B2 - Status: Granted - Kind: B2 - Application number: 12/810,417 - Filed: 2008-12-25 - Published: 2010-11-04 - Granted: 2013-09-24 - Earliest claimed: 2007-12-27 - Assignees: Seiko Epson Corporation - Applicants: Kazuo Okawa - Inventors: Kazuo Okawa - Web page: https://patentgrep.com/patent/US8541955B2 ## CPC - H05B 41/2887: {characterised by a controllable bridge in the final stage} - H02M 1/4225: {using a non-isolated boost converter} - H02M 7/53873: {with digital control} - H02M 1/007: {Plural converter units in cascade (push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826)} - Y02B 20/00: Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps - Y02B 70/10: Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - H02M: APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF (transformers H01F; dynamo-electric converters H02K47/00; controlling transformers, reactors or choke coils, control or regulation of electric motors, generators or dynamo-electric converters H02P) - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract Provided is an electric discharge lamp lighting device (10) including a control section (40) which performs first control operation for controlling at least the current value, frequency, duty ratio or waveform of a driving current (I) for driving an electric discharge lamp (90). The electric discharge lamp lighting device also includes a signal receiving section (50) for receiving a drive control signal (S) which can control at least the current value, frequency, duty ratio or waveform of the driving current (I) in mode different from the first control operation. The control section (40) performs second control operation for controlling at least the current value, frequency duty ratio or waveform of the driving current (I) based on the drive control signal (S), in the case where the signal receiving section (50) has received the drive control signal (S). ## Claims ### Claim 1 A discharge lamp lighting device comprising: a control section carrying out a first control operation which controls at least one of the current value, frequency, duty ratio, and waveform of a drive current for driving a discharge lamp; and a signal reception section receiving, from an exterior of the discharge lamp lighting device, a drive control signal for controlling the current value, frequency, duty ratio, and waveform of the drive current of a second control operation in a form differing from the first control operation, the drive control signal being an analog signal having a frequency corresponding to the frequency of the drive current of the second control operation, a duty ratio corresponding to the duty ratio of the drive current of the second control operation, an amplitude corresponding to the current value of the drive current of the second control operation, and a waveform corresponding to the waveform of the drive current of the second control operation, and in the event that the signal reception section has received the drive control signal, the control section, based on the drive control signal, carries out the second control operation which controls the current value, frequency, duty ratio, and waveform of the drive current. ### Claim 2 (depends on 1) The discharge lamp lighting device according to claim 1, further comprising: a storage section storing drive information relating to at least one of the current value, frequency, duty ratio, and waveform of the drive current, wherein in the event that the signal reception section has not received the drive control signal, the control section, based on the drive information stored in the storage section, carries out the first control operation which controls at least one of the current value, frequency, duty ratio, and waveform of the drive current. ### Claim 3 (depends on 1) The discharge lamp lighting device according to claim 1, further comprising: a conversion section that converts an analog signal into digital information, wherein the conversion section converts the analog signal received by the signal reception section into digital information, and the control section carries out the second control operation based on the digital information converted by the conversion section. ### Claim 4 (depends on 1) A projector comprising: the discharge lamp lighting device according to claim 1. ### Claim 5 (depends on 1) The method of claim 1, wherein the current value, frequency, duty ratio, and waveform of the drive control signal are determined in accordance with a lighting history of the discharge lamp. ### Claim 6 (depends on 1) The discharge lamp lighting device according to claim 1, further comprising: a determination section determining whether or not the signal reception section has received the drive control signal, wherein the control section, in the event that the determination section determines that the drive control signal has been received, carries out the second control operation, and in the event that the determination section determines that the drive control signal has not been received, carries out the first control operation. ### Claim 7 (depends on 6) The discharge lamp lighting device according to claim 6, wherein the determination section, in the event that the amplitude of the drive control signal has exceeded a threshold value, determines that the drive control signal has been received, and in the event that the amplitude of the drive control signal has not exceeded the threshold value, determines that the drive control signal has not been received. ### Claim 8 (depends on 1) The discharge lamp lighting device according to claim 1, wherein the drive control signal is supplied from a control section of a projector. ### Claim 9 (depends on 8) The discharge lamp lighting device according to claim 8, further comprising: an operation detection section which detects the drive voltage of the discharge lamp, and outputs drive voltage information, wherein the drive control signal is supplied from the control section of the projector based on the drive voltage information. ### Claim 10 (depends on 1) The discharge lamp lighting device according to claim 1, further comprising: a power control circuit generating discharge lamp drive power; and an alternating current conversion circuit generating and outputting the drive current for driving the discharge lamp by inverting the polarity of a direct current output by the power control circuit with a given timing, wherein the control section, by outputting to the power control circuit a current control signal for controlling the current value of the direct current, and outputting to the alternating current conversion circuit a control signal for controlling the timing of inverting the polarity of the drive current, controls at least one of the current value, frequency, duty ratio, and waveform of the drive current. ### Claim 11 (depends on 10) The discharge lamp lighting device according to claim 10, wherein the power control circuit includes a switching control power circuit which outputs the direct current, the control section, by outputting a pulse width modulation signal to the switching control power circuit as the current control signal, controls the current value of the direct current. ### Claim 12 (depends on 11) The discharge lamp lighting device according to claim 11, wherein the switching control power circuit is a step-down chopper circuit. ### Claim 13 (depends on 10) The discharge lamp lighting device according to claim 10, wherein the alternating current conversion circuit includes an inverter bridge circuit which generates and outputs the drive current. ### Claim 14 A method of controlling a discharge lamp lighting device outputting a drive current for driving a discharge lamp, comprising the step of: carrying out a first control operation controlling at least one of the current value, frequency, duty ratio, and waveform of the drive current; receiving, from an exterior of the discharge lamp lighting device, a drive control signal for controlling the current value, frequency, duty ratio, and waveform of the drive current of a second control operation in a form differing from the first control operation, the drive control signal being an analog signal having a frequency corresponding to the frequency of the drive current of the second control operation, a duty ratio corresponding to the duty ratio of the drive current of the second control operation, an amplitude corresponding to the current value of the drive current of the second control operation, and a waveform corresponding to the waveform of the drive current of the second control operation; and carrying out a second control operation for controlling the current value, frequency, duty ratio, and waveform of the drive current based on the drive control signal in the event that the drive control signal has been received.