Microchannel Plate Intensifier Assemblies
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Operating in the Soft X-ray Extreme UV or Vacuum UV requires specialized detection systems.
The growing popularity of charge coupled detectors (CCD) for multichannel detection is just as great in the extreme and vacuum ultraviolet region of the spectrum as it is in the UV-VIS-NIR. Difficulties are encountered with direct application of conventional detection schemes. Windows do not transmit, vacuum-sealing electronics can be problematic, and photo cathodes do not respond. To operate in the vacuum ultraviolet (1 to 200-nm) one method is to use an open microchannel plate (MCP) as an intensifier. Used before a conventional PDA or CCD the microchannel plate intensifier can convert invisible vacuum UV energy via phosphor to a visible emission. Then easily detected by Silicon based CCDs. The phosphor output can be coupled to the CCD by a lens transformer or by direct fiber coupling (preferred due to fewer losses). In this manner, an array detector can be constructed for wide wavelength coverage in the extreme and vacuum ultraviolet. The microchannel plate intensifier is a device that can also be gated or pulsed. This provides better time resolution than CCD detectors attain.
The Model 735 is a suitable high voltage power supply for proper operation microchannel plate intensifier assemblies.
| Part No. | MCP Diameter | Pore / Space (µm) | Stages | Gain | Output | Mounting | Phosphor |
| 8105-102356 | 40 | 10 / 12 | 2 | 1 x 10^6 | fiber taper to 25 mm | 4.5/4.625" CF | p22 |
| 8105-102357 | 40 | 10 / 12 | 1 | 1 x 10^3 | fiber taper to 25 mm | 4.5/4.625" CF | p22 |
| 8105-102358 | 40 Fast | 10 / 12 | 1 | 1 x 10^3 | fiber taper to 25 mm | 4.5/4.625" CF | p46 |
| 8105-102359 | 25 | 10 / 12 | 1 | 1 x 10^3 | straight 25 mm fiber | 4.5/4.625" CF | P22 |
On request, we offer many permutations of the listed assembleis. We can offer higher channel length to diameter ratio, 60:1. These are used to improve gain and also increases the tendency of the intensifier plate to exhibit ion feedback (either channel or phosphor generated.) The feedback will result in a 'glow' which will reduce the effective dynamic range of the MCP - possibly negating the increased gain potential.
Also, HOT(TM Galileo Electro Optics Corporation) plates exhibit the same quantum efficiency and gain characteristics as standard plates but due to the higher current capacity the MCP channels recharge / refresh faster for less sensitivity to saturation. Especially useful when encountering high count rates. HOT plates are also known as Extended Dynamic Range (Burle) plates and have a thicker lead zone to support higher strip currents.
| Feature | Option Code | Specification |
| Photocathode | CsI MgF2 Au | 1 to 250-nm 1 to 120-nm 20 to 120-nm |
| Phosphor Screen | P11, P20, P43, P46 | choose P46 for fast response (usec) and P43 for slow (msec) |
| Image Transfer | fiber optic | with conductive coating, transfers image outside vacuum, 40 to 25-mm tapers are common |
| Gating | Slow or Fast | Fast gating (10-nsec or less) may require strip, the entire intensifier can be pulsed for Slower gate times |
| Bake out | 200 or 350-deg Ct | all metal seal fritted assemblies are available for high temperature baking |
| Grazing Incidence | Yes | cut away retainer permitting grazing incidence access to microchannel plate surface |
| Power Attachment | Ground Front Ground Rear Ground Phos | no HV danger to user vacuum system independent power supplies, fast pulse counting with VIS images |
The Model 735 is a suitable high voltage power supply for proper operation microchannel plate intensifier assemblies.