# US 7,410,271 B1 · Flashlight with automatic light intensity adjustment means > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,410,271 B1 - Document ID: US7410271B1 - Status: Granted - Kind: B1 - Application number: 11/675,100 - Filed: 2007-02-15 - Published: 2008-08-21 - Granted: 2008-08-12 - Earliest claimed: 2007-02-15 - Assignees: Kaper Industrial Limited - Inventors: Shiu-Fai Stephen Man - Web page: https://patentgrep.com/patent/US7410271B1 ## CPC - F21L 4/005: {the device being a pocket lamp (F21L4/022, F21L4/045, F21L4/085 take precedence)} - F21V 23/0442: {activated by means of a sensor, e.g. motion or photodetectors} - H05B 45/00: Circuit arrangements for operating light-emitting diodes [LED] - H05B 45/12: using optical feedback - H05B 45/345: Current stabilisation; Maintaining constant current - F21Y 2115/10: Light-emitting diodes [LED] - F21L: LIGHTING DEVICES OR SYSTEMS THEREOF, BEING PORTABLE OR SPECIALLY ADAPTED FOR TRANSPORTATION - F21V: FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - F21Y: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED ## Abstract A flashlight with automatic light intensity adjustment means comprising a flashlight casing, a light source, a switch, a light controlling circuit on a printed circuit board and a power source, wherein a sensor component is attached to the flashlight casing, and the sensor component comprises a sensor casing and an incident light intensity sensor disposed therein, and the sensor is electronically connected to the light source, the switch, the light controlling circuit and the power source, and the light controlling circuit controls electrical current passing through the light source according to intensity of incident light as detected by the sensor so that more current is passed through the light source when a lower intensity of incident light is detected, and less current is passed through the light source when a higher intensity of incident light is detected. ## Claims ### Claim 1 A flashlight with automatic light intensity adjustment means which comprises a flashlight casing, a light source, a switch, a light controlling circuit on a printed circuit board and a power source, wherein a sensor component is attached to the flashlight casing, and the sensor component comprises a sensor casing and an incident light intensity sensor disposed therein, and the sensor is electronically connected to the light source, the switch, the light controlling circuit and the power source, and the light controlling circuit controls electrical current passing through the light source according to intensity of incident light as detected by the sensor so that more current is passed through the light source when a lower intensity of incident light is detected, and less current is passed through the light source when a higher intensity of incident light is detected. ### Claim 2 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the sensor casing is elongated in shape, and the sensor casing has an interior surface which is dark in color. ### Claim 3 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein a plurality of discs are disposed inside the sensor casing, and each of the discs is disposed with a center through hole so that light passes through the through holes before reaching the sensor. ### Claim 4 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the printed circuit board is disposed inside the flashlight casing, and the sensor is connected to the printed circuit board by means of wires passing through an opening in the flashlight casing. ### Claim 5 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the printed circuit board is disposed inside the sensor casing, and the sensor is connected to the printed circuit board by means of wires. ### Claim 6 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the light controlling circuit is configured to provide a current stabilizing function which stabilizes the electrical current passing through the light source when the intensity of incident light as detected by the sensor fluctuates. ### Claim 7 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the light controlling circuit is configured to provide a booster function, and a booster switch is provided on the flashlight casing for user to activate the booster function, and the booster switch and the switch are configured as two separate switches or incorporated as a single 3-way switch. ### Claim 8 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the sensor takes the form of a photoresistor. ### Claim 9 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the sensor takes the form of an infrared light sensor, and an infrared light emitter is disposed in the sensor casing to emit infrared light in a direction which is parallel to light emitted by the light source. ### Claim 10 (depends on 1) A flashlight with automatic light intensity adjustment means as in claim 1, wherein the light controlling circuit takes the form of an integrated circuit which is preset with one or more incident light intensity threshold levels, each of which corresponds to a preset level of electrical current to be controlled by the integrated circuit to pass through the light source.