To whom it may concern,

I'm looking for custom-cut optical filters that meet specific requirements for my startup's research initiative, and I'd like to ask for a quote:

Specifications Required:
- Central Wavelength: 850 nm
- Shape: Square
- Bandwidth/FWHM: Less than 30 nm ideally, the lower the better
- Angle of Incidence/AOI: 0° ± 30° ideally, or higher
- Transmission efficiency: Higher than 80%, higher the better
- Blocking level: At least OD3, but the higher the better
- Material: Preferably some type of coating/film over glass
- Price: Lowest possible, ideally less than $4 per unit in bulk.
- Dimensions: 3mm X 3mm (if not available: 4mm X 4mm, 4mm X 5mm, or 5mm X 5mm in order of preference). The photosensitive region is 2.85 mm X 2.85 mm.
- Quantity: 100-200 units

For each option, please provide any relevant optical properties, e. G bandwidth/FWHM, optical density, transmission efficiency, AOI, etc^

Inquiry Details:
- Lead Times: Please include estimated production and delivery schedules.
- Discounts: Information on any available bulk order discounts.

I'm currently evaluating multiple suppliers and would appreciate a prompt response, looking forward to your proposal.

Thank you for your attention.