SINGLE-LENS PATHWAY FOR EMISSION AND EXCITATION USING A MIRROR AND BEAM SPLITTER IN A CUSTOMIZABLE OPTICAL HEAD

1 . A small form factor optical head defining a single light pathway, comprising:

a housing;

a lens positioned on or in the housing;

a light source positioned in the housing, the light source configured to emit an excitation light;

a mirror positioned in the housing to reflect the excitation light to the lens and to receive emission light back through the lens;

a beamsplitter positioned in the housing to direct the excitation light to the lens and to direct the emission light; and

a detector positioned to receive emission light after passing back through the lens and the beam splitter,

wherein the lens, the mirror, and the beam splitter define a single light pathway for the excitation light and emission light.

2 . The optical head of claim 1 , wherein the lens is adjustable.

3 . The optical head of claim, wherein the lens is a ball lens.

4 . The optical head of claim 1 , wherein the excitation light is provided by a LED.

5 . The optical head of claim 1 , wherein the excitation light is provided by a laser.

6 . The optical head of claim 1 further including one or more filters.

7 . The optical head of claim 6 , wherein the one or more filters includes an emission filter and/or an excitation filter.

8 . The optical head of claim 1 further including a lens block.

9 . The optical head of claim 8 , wherein the mirror and the beamsplitter are received in a first side of the lens block and the lens is in or on a second side of the lens block.

10 . The optical head of claim 8 , wherein the lens block includes a first lens block section configured to receive the light source, a second lens block section configured to receive one or more filters, and a third lens block section configured to receive the mirror and the beamsplitter.

11 . The optical head of claim 8 , wherein the first, second, and third lens block sections are secured to one another and positioned in the housing as a unit.

12 . The optical head of claim 1 , wherein the detector is a photodiode.

13 . A small form factor optical head defining a single light pathway, comprising:

a housing;

a lens;

a light source positioned in the housing;

a photodiode positioned in the housing;

a lens block positioned in the housing;

a mirror positioned in the housing;

first and second filters positioned in the housing;

wherein the lens block is configured to receive the light source, the photodiode, the first and second filters, the mirror and the beamsplitter in a first side thereof and the lens is positioned at a second side thereof,

wherein the lens is configured to focus the excitation light and to allow emission light to pass through the lens,

wherein the beam splitter directs the excitation light toward the lens, and directs emission light to a detector.

14 . The optical head of claim 13 , wherein the single lens is a ball lens.

15 . The optical head of claim 13 , wherein the lens is adjustable.

16 . A method for optical analysis, comprising:

providing an optical head having a housing, a lens positioned on or in the housing, a light source positioned in the housing, the light source configured to emit an excitation light, a mirror positioned in the housing to reflect the excitation light to the lens and to receive emission light back through the lens, a beamsplitter positioned in the housing to direct the excitation light to the lens and to direct the emission light, and a detector positioned to receive emission light after passing back through the lens and the beam splitter, wherein the lens, the mirror, and the beam splitter define a single light pathway for the excitation light and emission light;

emitting a light beam from the light source;

receiving an emission beam; and

analyzing the emission beam.