
( Brand: Midopt ), ( Manufacturer Part Number: LP1070-37.5 ), ( Part Type: Filter Short ), ( Filter Effects: Infrared )
The **Midopt Midwest Optics LP1070-37.5** is a high-performance **short-wave infrared (SWIR) longpass filter** engineered for precision optical applications requiring strict spectral control in the near-infrared and shortwave infrared regions. Designed with a **cut-on wavelength of 1070 nm**, this filter effectively blocks all light below this threshold while transmitting wavelengths longer than 1070 nm with minimal absorption, making it ideal for imaging, spectroscopy, and laser-based systems where spectral purity is critical. Constructed from **optically polished glass substrates** with a durable, multi-layer dielectric coating, the LP1070-37.5 ensures consistent performance across a broad spectral range, from approximately 1070 nm to beyond 2000 nm, with an **optical density (OD) of 4 or greater** at wavelengths shorter than the cutoff guaranteeing near-complete rejection of stray or unwanted radiation. The filter s **37.5 mm diameter** provides ample clear aperture for most standard optical setups, including cameras, sensors, and telescopes, while its **thin profile** minimizes bulk without compromising structural integrity. Suitable for use in **harsh environments**, including industrial, aerospace, and scientific research applications, the LP1070-37.5 is coated with an **anti-reflective (AR) layer** on both surfaces to reduce surface reflections and maximize throughput in the transmission band. Whether integrated into a **SWIR camera system, laser protection setup, or high-precision spectroscopic analyzer**, this filter delivers exceptional spectral fidelity, low polarization sensitivity, and long-term stability, making it a reliable choice for demanding optical filtering requirements.
### **Pros and Cons of buying a MidOpt LP1070-37.5 (Short-Wave Infrared Longpass Filter)**
#### **Pros:**1. **High Optical Quality** MidOpt is a reputable manufacturer known for precision optical coatings and minimal distortion. The LP1070-37.5 is designed for high transmission in the near-infrared (NIR) and short-wave infrared (SWIR) ranges while blocking visible and longer wavelengths, making it suitable for applications requiring clean spectral separation.
2. **Specific Wavelength Cutoff** The 1070 nm cutoff is useful for applications where visible light must be blocked while allowing SWIR or NIR light to pass. This is particularly valuable in:
- **Thermal imaging** (where blocking visible light reduces glare and improves contrast).
- **Medical imaging** (e.g., fluorescence imaging, where specific NIR wavelengths are isolated).
- **Astronomy** (for blocking ambient light while capturing SWIR signals).
- **Security and surveillance** (where IR-sensitive cameras need to avoid visible light interference).
3. **Durable and Stable Coating** MidOpt s coatings are designed to resist environmental factors like moisture, dust, and temperature fluctuations, ensuring long-term performance.
4. **Compatibility with Common Optical Systems** The filter s dimensions (37.5 mm) make it suitable for standard optical mounts, lenses, and filter holders, reducing the need for custom adaptations.
5. **Cost-Effective for Specialized Applications** While not the cheapest filter on the market, it offers a balance between performance and price for users who require a reliable SWIR longpass filter without investing in high-end research-grade optics.
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#### **Cons:**1. **Limited Visible Light Blocking** The LP1070-37.5 is optimized for SWIR/NIR applications but may not provide perfect blocking of all visible light, especially near the cutoff region (900 1100 nm). Users requiring stricter visible rejection (e.g., for high-contrast imaging) may need additional filters or bandpass combinations.
2. **Potential for Reflection and Ghosting** Like all optical filters, it may introduce some back-reflection or ghosting, which could affect image quality in high-precision applications. Anti-reflection (AR) coatings can help, but they may increase cost.
3. **Size Constraints** The 37.5 mm diameter limits its use in compact or space-constrained systems. Smaller or larger formats may be required for certain applications.
4. **No Built-in UV Blocking** If the application involves UV light, additional filters will be needed, as the LP1070-37.5 does not inherently block UV wavelengths.
5. **Requires Proper Alignment** Like any optical component, misalignment or improper mounting can degrade performance. Users must ensure precise installation to avoid vignetting or uneven light transmission.
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### **Conclusion and Recommendation**
The **MidOpt LP1070-37.5** is a **high-quality, reliable longpass filter** well-suited for applications requiring the isolation of SWIR/NIR light while blocking visible wavelengths. It excels in **thermal imaging, medical diagnostics, astronomy, and security systems** where a clean spectral cutoff is critical.
**Recommendation:** - **Buy if:**- You need a **cost-effective, mid-range filter** for SWIR/NIR applications where visible light rejection is a priority.
- Your system can accommodate the **37.5 mm size** and requires minimal additional filtering.
- You prioritize **optical clarity and durability** over ultra-narrowband performance.
- **Consider alternatives if:**- You need **perfect visible light blocking** (e.g., for high-contrast imaging), in which case a **shortpass filter or bandpass combination** may be better.
- Your budget allows for **custom or research-grade filters** with tighter specifications.
- You require **UV blocking**, as this filter does not address that range.
For most **general-purpose SWIR/NIR applications**, the **MidOpt LP1070-37.5 is a solid choice** that balances performance and affordability. However, always verify compatibility with your specific optical setup before purchasing.
All MidOpt filters can also be purchased unmounted and in custom dimensions upon request from Machine Vision Direct. Because silicon is inherently opaque, blocking in the visible and very near-IR spectrum's excellent, positioning of cut-on slope completely insensitive to angle incidence light impinging on surfaces. LP1070 also reduces Nd:YAG 1064nm light transmission by approximately 50%. Very lightly used - purchased for a prototype that was tested few weeks.
No scratches on either side of optic - excellent condition. Typically $259 new. Manufacturer: The MidOpt LP1070-37.5 is a 0.7mm thick silicon longpass filter with anti reflection coatings on both sides, optimized for 1100-2300nm transmission.