Ultra compact 8mm KD*P Pockels cell with integrated polarizer and waveplate for Q-switching
Prompted by a need for even smaller components than our model EM510C we have developed this latest model EM508UC to provide a full, 8mm aperture in a package only 19mm diameter yet it also packs a factory pre-aligned thin film Brewster plate polarizer and quarter wave retardation plate making it ideal for pulsed quarter wave Q-switching.
The Brewster polarizer is required when Q-switching laser media that do not have strongly polarized gain cross-sections and of course, Nd:YAG is a classic example (Nd:YVO4 would not require the polarizer). The retardation plate is usually oriented towards the rear mirror so P-polarized light which passes through the polarizer during the pump phase is converted to S-polarization after a double pass and is rejected from the cavity by the polarizer. The cavity therefore experiences high loss during this phase. The application of a fast rise time (ask about our drivers) quarter wave pulse means that P-polarized light passing through the polarizer is no longer switched to S-polarization so this then experiences minimum loss and the P-polarization is then allowed to be amplified in the cavity and the giant, Q-switched pulse is produced.
Ultra compact 8mm KD*P Pockels cell with integrated polarizer and waveplate for Q-switching
Both the Brewster thin-film polarizer and the low order quarter wave retardation plate will be pre-aligned with the axes of the KD*P crystal. The standard orientation is for transmitted P-polarization to be parallel to the axis of the connecting studs, but if you prefer we can orientate the studs at 90° to the polarizing optical elements on request.
Provisional Specifications
| Parameter | EM508UC |
|---|---|
| Aperture: | 8mm |
| Wavelength Range: | 1064nm * |
| Halfwave Voltage @ 1.06μm: | Approximately 6.2 kV static, 7.5kV dynamic |
| Maximum Voltage: | 8kV |
| Optical Rise Time: | < 1.0 ns |
| Contrast Ratio @ 1.06μm: | > 1000:1 |
| Capacitance Unterminated: | < ~5 pF |
| Damage Threshold: | 600 MW/cm2 |
| Insertion loss (P-polarization): | 4% |
| Extinction ratio: | >300:1 ** |
| EM508UC Interface Drawing |
** Polarizer limited
Application Notes for Pockels Cells:
The Linear Electro-Optic Effect
Selecting the Right Pockels Cell
Setting Up the Q-Switch
Pulse Slicing with Pockels Cells
Pulse Picking with 4 Terminal Pockels Cells