LED-based lighting fixtures for surface illumination with improved heat dissipation and manufacturability

A lighting apparatus, comprising:

• a heat sink having a first surface;
• an LED printed circuit board having second and third opposing surfaces, wherein the second surface is disposed on the first surface of the heat sink and wherein the third surface has at least one LED light source disposed thereon;
• an integrated lens-housing member having a transparent upper wall disposed to receive light emitted by the at least one LED light source;
• a pressure-transfer member having a support structure extending generally in the direction from the LED printed circuit board to the transparent upper wall of the integrated lens-housing member and further having a pressure-transfer surface connected to the support structure, wherein the support structure defines an aperture, and wherein the pressure-transfer surface is disposed on the third surface of said LED printed circuit board and further disposed proximate to the LED light source;
• and
• an optic member disposed in the aperture defined by the support structure of the pressure-transfer member,
• wherein the integrated lens-housing member is compressively coupled to the pressure-transfer member, such that a force exerted by the integrated lens-housing member is transferred via the pressure-transfer member to the pressure-transfer surface so as to press the LED printed circuit board toward the first surface of the heat sink, so as to provide for heat transfer from the LED printed circuit board to the heat sink, and
• wherein the transparent upper wall of the integrated lens-housing member has an inner surface having at least one connecting pin, and further comprising a light diffusion layer disposed on the inner surface of the transparent upper wall, the connecting pin being configured to hold the light diffusion layer against the inner surface of the transparent upper wall.