BP470
Blue Bandpass Filter

Recommended for use with 470nm blue LEDs and for UV fluorescence imaging

BP470 filters are recommended for use in most blue LED (~470nm) and many UV-excited blue fluorescence (430 - 500nm) imaging applications. Important for both applications is the breadth of the bandwidth. In the case of blue LEDs, frequent variations in center wavelengths and angles of incidence can easily be accommodated. BP470 ABSORBS lower wavelengths (e.g., UV) and REFLECTS longer wavelengths (e.g., 500-1150nm). This material does not auto-fluoresce.

For typically weak blue fluorescence applications, it is important to be able to detect as much of the blue emission as possible while effectively blocking all of the UV light. Since more than 90% of all industrial UV fluorescence applications involve imaging a blue-colored “glow,” it can be summarized that most applications involving a UV light REQUIRE the use of a BP470 filter. Without this filter, it is virtually impossible to successfully image the desired feature.

We recommend our BP470 blue bandpass filter over all other blue filters because of its broad peak (T>90%), high transmission, far superior blocking of shorter UV and longer IR wavelengths, and far steeper cut-on and cut-off slopes. All of this results in far brighter, higher contrast images when using the BP470 compared to other filters currently available.

These single substrate, hard-coated filters are about 2mm thick and can withstand very high temperatures. The coatings are just as or MORE durable than the glass. Therefore the limiting factor is the transformation temperature and thermal gradient/shock values for the glass.

Example:

(left) Monochrome image with white light.
(center) Photographic filter doesn't help at all.
(right) MidOpt BP470 clearly brings out the batch code for machine reading.

More examples

Download Excel Spreadsheet with data and curve for this filter.

Standard Threaded Mounts:
We offer standard filter sizes from stock – 22.5mm to 62mm – for same- or next-day shipping. Larger filters – 67mm to 105mm – are made to order and are normally not returnable.

Click here for PDF drawing of standard mounts

Slip Mounts:
If your lens does not have threads for mounting a filter, Slip Mount adapters are available. Slip Mounts can attach a regular filter to a lens or attach a very large filter to accommodate a wide angle lens. Please call to order Slip Mount adapters.

C-Mounts:
3mm thick threaded mount for adding a filter between lens and camera
Click here for PDF drawing of c-mounts

Transmission chart (typical)
Passes 435-490nm
Absorbs UV 270-380nm
Reflects most visible and IR

1100
1090
1080
1070
1060
1050
1040
1030
1020
1010

1000
990
980
970
960
950
940
930
920
910

900
890
880
870
860
850
840
830
820
810

800
790
780
770
760
750
740
730
720
710

700
690
680
670
660

1.61
1.44
0.76
0.37
0.20
0.13
0.11
0.10
0.11
0.16

0.30
0.98
2.55
0.85
0.40
0.32
0.42
0.96
3.35
1.65

0.65
0.51
0.67
1.23
1.42
0.78
0.58
0.65
1.07
1.97

0.98
0.23
0.22
0.29
0.40
0.13
0.05
0.02
0.04
0.08

0.03
0.00
0.00
0.00
0.07

650
640
630
620
610
600
590
580
570
560

550
540
530
520
510
500
490
480
470
460

450
440
430
420
410
400
390
380
370
360

350
340
330
320
310
300
290
280
270
260

250
240
230
220
210

0.01
0.00
0.00
0.03
0.15
0.05
0.07
0.09
0.06
0.08

0.10
0.20
0.44
1.09
9.28
47.75
89.01
88.66
90.52
90.09

92.03
92.61
91.87
50.00
3.65
0.00
0.00
0.00
0.00
0.00

0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00

0.00
0.00
0.00
0.00
0.00