Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Yasuhisa Ueda

Takaari Uemoto

Masahiro Miki

Kazushige Sugita

Toshiaki Isogai

Hideo Nagai

Kazuhiro Kawabata

A lighting circuit () includes a controller integrated circuit (U) for on and off control of a switching element (Q), a transformer (T) having a primary coil (T) that is connected in series to the switching element and a secondary coil (T), a first voltage supply circuit supplying a voltage that occurs across both ends of the primary coil to an LED module (), and a second voltage supply circuit supplying a voltage induced in the secondary coil to a power source terminal (Vcc) when the switching element is on. A turns ratio N of the primary coil to the secondary coil satisfies Equation 1, where X1 V denotes a voltage that an AC power source supplies, Y V denotes the maximum value of a power source voltage of the control unit at which normal operation is guaranteed, and Z V denotes the minimum value of the power source voltage.

Lighting circuit and lamp

A lamp includes an LED module, a drive unit supplying power to the LED module, and a base via which power is fed from an external power supply to the drive unit. The drive unit is located between the LED module and the base. The drive unit includes a circuit board having a main surface on which lead-type electronic components are mounted, lead wires (first lead wires) extending from the main surface of the circuit board and connected to the LED module, and lead wires (second lead wires) extending from the main surface of the circuit board and connected to the base. The circuit board has a through-hole extending from the main surface to an opposite surface thereof. The lead wires pass through the through-hole.

Light

A lamp includes a semiconductor light-emitting element, a light guiding element, a wavelength converter, a reflecting mirror, and a circuit unit axially disposed within a central section of the outer tube of an envelope. Light emitted by the semiconductor light-emitting element is guided by the light guiding element to be incident on and be converted by the wavelength converter. At least one component of the circuit unit is disposed at a side of the wavelength converter opposite the semiconductor light-emitting element. The reflecting mirror is disposed between the at least one component of the circuit unit and the wavelength converter, and reflects at least part of light received from the wavelength converter back toward the wavelength converter.

Semiconductor lamp with wavelength converter and circuit component axially opposed from light source

A lampincludes a semiconductor light-emitting elementas a light source, a circuit unitthat causes the semiconductor light-emitting elementto emit light, and an envelopehaving an outer tubeand a base. The semiconductor light-emitting elementand the circuit unitare housed in the envelope. The semiconductor light-emitting elementis disposed in a region at a side of an axially central section of the outer tubefacing the baseand oriented so that a main emission direction points away from the base. At least one component of the circuit unitis disposed in a region at a side of the axially central section of the outer tube opposite the semiconductor light-emitting element. A light guidethat guides emission light of the semiconductor light-emitting elementalong the axial direction is disposed between the at least one component of the circuit unitand the semiconductor light-emitting element. The light guidehas a light-diffusing portion corresponding in position to the axially central section of the outer tube

Growing community of inventors

Osaka, Japan

Yasuhisa Ueda