Resin-sealed laser diode device

A resin-sealed laser diode device, comprising:

• a laser diode chip having front and rear light-emitting end faces through which a laser beam from an active layer is emitted forwardly and backwardly;
• end-face protecting films protecting said light-emitting end faces;
• a lead frame supporting said chip through a supporting substrate;
• a sealing resin sealingly isolating said chip from outside air;
• and
• an end-face breakage preventing film of organic silicone resin low in an absorption coefficient to a band of wavelengths of said laser beam, for preventing said sealing resin near said light-emitting end faces from being damaged by said laser beam,
• wherein said organic silicone resin is like rubber and contains dimethyl polysiloxane, and
• wherein said laser diode chip is mounted on said lead frame being shifted inwardly from an end of said lead frame to the extent that a laser beam emitted through said front light-emitting end face of said chip is not substantially blocked by said lead frame.

A resin-sealed laser diode devices, comprising:

• a laser diode chip having front and rear light-emitting end faces through which a laser beam from an active layer is emitted forwardly and backwardly;
• end-face protecting films protecting said light-emitting end faces;
• a lead frame supporting said chip through a supporting substrate;
• a sealing resin sealingly isolating said chip from outside air;
• and
• an end-face breakage preventing film of organic silicone resin low in an absorption coefficient to a band of wavelengths of said laser beam, for preventing said sealing resin near said light-emitting end faces from being damaged by said laser beam,
• wherein said organic silicone resin is like rubber and contains dimethyl polysiloxane;
• and
• wherein a position of said laser diode chip mounted on said lead frame is defined by the following expression:
• 0<X<L cot(θv/2)
• where X is a distance between said laser diode chip and the end of said lead frame, L is a distance between said lead frame and said active layer, and θv is a full width angle at half maximum, in a vertical emission direction, of said laser beam.