Method and apparatus for pulsed L.E.D. illumination for a camera
First Claim
1. An electronic camera and LED-illumination apparatus, comprising:
- a housing of such compact size and low weight as to be suitable for single-handed portable operation by a user, and configured to hold a battery;
an imaging device mounted to the housing, wherein the imaging device is configured to generate an electronic image signal based on light gathered during a time window;
at least one LED mounted to the housing; and
a control circuit having an electronic switch operatively coupled to alternately connect and disconnect electrical power from the battery to the control circuit, such that the control circuit selectively applies electrical power from the battery to the at least one LED in synchrony with the time window during which light is gathered, wherein the control circuit controls LED light output to obtain an accumulated light input characteristic to the imaging device as a voltage of the battery varies over a range that would otherwise vary the light input characteristic by adjusting a proportion of connect time to disconnect time of the electronic switch.
3 Assignments
0 Petitions
Accused Products
Abstract
An illumination source for a camera includes one or more LEDs, and an electrical circuit that selectively applies power from the DC voltage source to the LEDs, wherein the illumination source is suitable for handheld portable operation. In some embodiments, the electrical circuit further includes a control circuit for driving the LEDs with electrical pulses at a frequency high enough that light produced has an appearance to a human user of being continuous rather than pulsed, the control circuit changing a pulse characteristic to adjust a proportion of light output having the first characteristic color spectrum output to that having the second characteristic color spectrum output. Some embodiments provide an illumination source including a housing including one or more LEDs; and a control circuit that selectively applies power from a source of electric power to the LEDs, thus controlling a light output color spectrum of the LEDs.
-
Citations
24 Claims
-
1. An electronic camera and LED-illumination apparatus, comprising:
-
a housing of such compact size and low weight as to be suitable for single-handed portable operation by a user, and configured to hold a battery; an imaging device mounted to the housing, wherein the imaging device is configured to generate an electronic image signal based on light gathered during a time window; at least one LED mounted to the housing; and a control circuit having an electronic switch operatively coupled to alternately connect and disconnect electrical power from the battery to the control circuit, such that the control circuit selectively applies electrical power from the battery to the at least one LED in synchrony with the time window during which light is gathered, wherein the control circuit controls LED light output to obtain an accumulated light input characteristic to the imaging device as a voltage of the battery varies over a range that would otherwise vary the light input characteristic by adjusting a proportion of connect time to disconnect time of the electronic switch. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
-
-
9. An apparatus for providing general-purpose illumination of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:
-
a housing configured to be held in a single hand; at least one LED that emits light when driven by an electrical current, wherein the at least one LED is mounted to the housing; a battery connection mounted to the housing for coupling electrical current from a battery; an electronic camera mounted to the housing, wherein the camera is configured to generate an electronic image signal based on light gathered during a time window; means for electronically switching to alternately connect and disconnect current in an electrical path between the battery and the at least one LED; and means for selectively applying electrical current from the battery to the at least one LED synchronized with the time window, wherein the means for selectively applying electrical current controls LED light output to obtain an accumulated light input characteristic to the electronic camera as a voltage of the battery varies over a range that would otherwise vary the light input characteristic by adjusting a proportion of connect time to disconnect time of the electronic switch. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
-
-
17. A method of providing illumination for an electronic camera of such compact size and low weight as to be suitable for single-handed portable operation by a user, comprising:
-
providing at least one LED in a housing configured to be held in a single hand, wherein each of the at least one LED emits light when driven by an electrical current; connecting a battery to the housing; electronically switching to alternately connect and disconnect an electrical-current path between the battery and the at least one LED to control one or more pulses of electrical current to the at least one LED; emitting light from the at least one LED based on the one or more pulses of electrical current to illuminate an object; gathering light from the illuminated object during a time window and generating an electronic image signal of the object illuminated by the emitted light based on the light gathered during the time window; synchronizing the emitting of light from the at least one LED with the time window for gathering light; and controlling, across a battery-voltage range that would otherwise vary an intensity of LED light output, the electronic switching to generate an amount of light output from the at least one LED sufficient to provide a desired accumulation of the light gathered for the generating of the electronic image signal. - View Dependent Claims (18, 19, 20, 21, 22, 23, 24)
-
Specification