LEX3 is a new LED illumination system using a high-powered LED chip. It has been designed to offer brighter and more stable lighting than the previous LED system. There are two models available: blue (peak: 465nm) and green (peak: 530nm).
LEX3 features a high-powered LED chip and original feedback mechanism for maintaining stable light intensity. It is our best LED system in terms of brightness and stability, resulting in very good signal to noise ratios.
LEX3 can be used for many biological applications. It can be used with MiCAM high speed imaging systems as an excitation light source for detecting fluorescent signals, or as a light stimulator for cells that express light-activated proteins in electrophysiological experiments.
High Power
LEX3 consists of a high-powered LED chip, which produces a light intensity over 360mW/cm2. It is approximately 2.3 times brighter than 150W halogen light source.
The intensity can be simply adjusted with coarse/fine dials on the front panel in the range between 0 and 150% (100% to 150% intensity can be used for short-pulse illumination lasting less than 1 second).
Comparison of light intensity (mW/cm2) between LEX3 green LED Light system and 150W halogen lamp system (with green filter) at 100% intensity.
High Stability of Light Intensity through Feed-Back Mechanism
The intensity is more stable than halogen lamps and does not produce any flicker or large arc fluctuations, in comparison to Xenon and Mercury light sources. LEDs are an ideal illumination source for high speed imaging. However, light intensity of LEDs tends to decrease when turned on for long periods of time, due to the heat of LED chips. To keep light intensity constant, LEX3 adopts an original feedback technology. This feedback mechanism results in less than ±0.3% drift within 30 seconds at 50 % intensity.
Change in light intensity within 30 seconds at 50% intensity. Measured with fast CCD imaging system, MiCAM02-HR (30 seconds at 100 frames/second, 4 times averaging).
Synchronized Illumination with external signal
The light can be turned ON/OFF by signals from external devices such as MiCAM high speed imaging systems or pulse generators. By sending a pulse greater than 1.5V through a BNC connector to the front panel of MiCAM high speed imaging systems, the light can be activated. LEX3 does not use any mechanical shutter, so there is no noise caused by vibration or sound.
Adjustment of the light intensity by external signal
Light intensity can be controlled by analog voltage signal from external device. 3.3V voltage input can set about 100% light intensity.
Monitor function for light intensity setting
LED intensity adjustment control can be monitored through a BNC connector. At 100% intensity setting, outputted voltage is 3.3V.
- Excitation light source for MiCAM high speed fluorescence imaging systems using indicators including voltage-sensitive dyes, calcium indicators, and genetically encoded optical probes such as voltage-sensitive proteins.
- Light source for stimulation to light-activated protein such as channelrhodopsin 2 (ChR2) and halorhodopsion (NpHR) (used in the following papers).
– 「Crystal structure of the channelrhodopsin light-gated cation channel.」
– 「Synaptic and network consequences of monosynaptic nociceptive inputs of parabrachial nucleus origin in the central amygdala.」 - Other imaging applications requiring stable and bright light.
| Item | LEX3-B | LEX3-G |
|---|---|---|
| Center Wavelength | 465 nm | 530 nm |
| LED intensity at 100% setting (*1) |
approx. 550 mW/cm2 | approx. 400 mW/cm2 |
| LED intensity at 150% setting (*1) |
approx. 600 mW/cm2 | approx. 450 mW/cm2 |
| Light Fluctuation (*2) | approx. <±0.015% | |
| Change in light intensity in 30 seconds (*2) |
approx. <±0.3% | |
| Intensity stabilization system | PD feedback circuit | |
| LED On/Off Control | By safety key switch | |
| Shutter Control | Manual control: Key switch on the front panel External control:triggered by over 1.5V input |
|
| Intensity Control | Manual control: 0-100%, 100%-150% (only for short-pulse illumination) External control: 0-150% control by voltage input (100% intensity by 3.3V input) |
|
| Monitoring Output | Output of voltage signal (3.3V output at 100% intensity) | |
| Protection Function | Overcurrent protection, overheat cutoff | |
| Light Guide Connector | Safety interlock included | |
| Light Guide | Sold separately | |
| Environmental Conditions | Indoor use, temperature 0℃ to 35℃ Humidity 0 to 70% | |
| Cooling Methods | By fan | |
| Dimensions and Weight | 150mm(W) x 250mm(D) x 83mm(H) / 2kg | |
| Input Voltage and Power Consumption | 100-220V, 30W | |
(*1) Measured value at output end of straight light guide (glass type, bundle diameter of 10mm, length of 2200mm ).
(*2) <50% intensity. Measured with fast CCD imaging system, MiCAM02-HR (30 seconds at 100 frames/second, 4 times averaging).